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Organic Chemistry 有机化学双语教学 习题（部分）

王 梅

大连理工大学

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Chapter 1 Introduction 1. Explain the following terms accurately and concisely.

1) organic chemistry and organic compounds 2) covalent bonds and polar bonds 3) bond energy and bond angle 4) structural formula 5) homolytic cleavage and heterolytic cleavage 6) active intermediate 7) electrophile and nucleophile 8) static inductive effect 9) protic solvent and solvent 10) solvation

2. Show the direction of the dipole moment for the following compounds.

CH3OH CH3OCH3

3. Explain whether the bonds in these compounds would be ionic or covalent and show Lewis structures for them:

(a) KCl (b) NCl3

4. What is the formula for the simplest neutral compound formed from P and H? Show a Lewis structure for this compound and predict its shape.

5. Compare the values of the dipole moments for CH2Cl2 and CHCl3.

6. Show Lewis structures for these compounds:

(a) CH5N (b) C2H5Cl (c) N2 (d) CH3N (e) C2H3F (f) CH4S

7. Explain which of the two following structures would be more stable. Explain whether they represent isomers or are resonance structures.

CO

H N H

H

..:

CO

H N H

H

..::

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8. Draw a Lewis structure for carbon monoxide (CO). Calculate the formal charges on the atoms and comment on the stability of this compound. 9. Determine whether the following pairs of structures are actually different compounds or simply resonance forms of the same compounds.

10. (a) Show the unshared electron pairs on the following anion. The S has a formal charge of –1, and the formal charge of the other atoms are zero.

C

H

H C

H

O

S (b) Draw a resonance structure for this ion.

11. Show a Lewis structure for C2H6O in which both carbons are bonded to the oxygen. What is the geometry to this molecule at the oxygen? Show the direction of the dipole for the molecule. 12. Ozone, O3, is a form of oxygen found in the upper atmosphere. It has the connectivity O-O-O. (a) Show a Lewis structure for ozone. (b) (b) Calculate the formal charge on each oxygen of ozone. (c) What is the shape of ozone? (d) (d) Experimental observations show that both bonds of ozone are identical. Explain how this

is possible. 13. Explain how the dipole moments of FCl (0.9 D) and ICl (0.7 D) can be so similar. 14.Chlorine is more electronegative than phosphorus. Predict the dipole moment of PCl5. 15. Show a Lewis structure for NO2

−. (Both oxygens are bonded to the nitrogen.) Show a resonance structure also.

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16. A covalent ion can also have polar bonds. Consider the ammonium cation. How are its bonds polarized? Do you think that the N of the ammonium cation is more or less “electronegative” than the N of ammonia (NH3)? Would the hydrogens of NH4

+ or NH3 have a larger partial positive charge? 17. Draw the important resonance forms to show the delocalization of charges in the following ions.

18. Use heavy and dashed wedged lines to show the shapes of the following molecules. Show the bond dipole of each polar bond and show the overall dipole of each molecule.

C

H

H N

H

H

H

..C

F

FF

F

(a) (b) (c)

C

H

H C

H

H

O.. :

19. Draw complete Lewis structures, including lone pairs, for the following compounds.

20. (a) Write a Lewis structure for sulfur dioxide in which the octet rule is satisfied for all three atoms. Show all electron pairs and include any formal charges. The atoms are connected in the order OSO.

(b) The octet rule may be violated for elements beyond the second period of the periodic table. Write a Lewis structure for sulfur dioxide in which each oxygen is connected to sulfur by a double bond. Show all electron pairs and formal charges.

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21. Designate which of the following pairs represent(s) resonance structures.

CH2=CH2 and CH2-CH2. .

CH3CHCH2

CH3

CH2CHCH3

CH3

and

A BCH3 C=CH2

OHand CH3CCH3

O

H2C N N.. H2C N N..and

DC

..

Chapter 2 Organic compounds: A first look 1. Which of the following compounds and ions are nucleophiles and which are electrophiles? Which are both nucleophiles and electrophiles? Which is neither nucleophile nor electrophile?

H+ Br+ H2O ROH HCN RCH2Cl RCH2−

+NO2 −OH −NH2 NH3 CH4 H2 2. Why the reaction activity for the anion is bigger in aprotic solvents (such as DMSO) than that in protic solvents (such as ethanol)? 3. Estimate the enthalpy value for the following reaction and judge if the reaction is endothermic or exothermic?

CH4 + Br2 CH3Br + HBr 4. There are eight structural isomers that have the formula C5H11Cl. Show a structure for each of them. 5. Calculate the DU for these formulas and draw two structural isomers for each: (a) C10H22 (b) C9H16 (c) C6H6 6. What kinds of attractive intermolecular forces are found in each of these compounds? (a) CH3CH2CH3 (b) CH3OCH3 (c) CaCl2 (d) CH3OH 7. Draw all isomers with each of these formulas. The total number for each is given in parentheses. (a) C3H8O (3) (b) C4H9Cl (4) (c) C4H8 (5) (d) C7H16 (9)

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8. For each pair of ions, determine which ion is more stable. Use resonance forms to explain your answers.

9. There are lots of isomers with the formula C4H8O. (a) Draw three that have a carbon-oxygen double bond. What functional group is present in each

of them? (b) Draw three alcohols with this formula. (c) Draw an ether with this formula that does not have a carbon-carbon double bond. 10. Calculate the DU for each of these formulas and draw a structure that meets the listed restriction: (a) C5H9NO (not an amine) (b) C7H12O (a ketone) (c) C6H14) (does not hydrogen bond) (d) C7H8 (an aromatic compound) 11. Is it possible for C8H17N to have a nitrile as its functional group? Explain. 12. One of these isomeric alcohols has mp = 26°C and bp = 82 °C; the other has mp = -90°C and bp = 117°C. Explain which isomer has the higher melting point and which has the higher boiling point.

OH OH

13. Explain the differences in the boiling points between the members of each of these pairs of compounds: (a) CH3(CH2)6CH3, bp: 126°C and CH3(CH2)8CH3, bp: 174°C (b) CH3CH2CH2OH, bp: 97°C and CH3CH2OCH3, bp: 11°C (d) CH3CH2CH3, bp: -42°C and CH3OCH3, bp: -23°C 14. Because of two hydrogen bonds, carboxylic acids show a very strong attractive force between two molecules that persists even in the gas phase. Show this hydrogen bonding between two carboxylic acid molecules.

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15. Explain the difference in the melting points of these isomers:

mp = −140 °C mp = 7°C 16. Bond strengths can be used to estimate whether a reaction is energetically favorable or not – that is, whether the reactants or the products are more stable. Use bond dissociation energies to determine whether this reaction is energetically favorable. The bond dissociation energy for H2 is 104 kcal/mol (435 kj/mol.

CH2=CH2 + H−H CH3-CH3

17. Write the structural formulas of alkanes matching the following factors and name them by systematic nomenclature. 1） pentane with only primary hydrogen atoms 2） pentane with a tertiary hydrogen atom 3） hexane with primary and secondary hydrogen atoms 4） hexane with only a carbon atom 5） hexane with a quaternary carbon atom 6） pentane with only one product by monochlorination 7） pentane with only three products by monochlorination 8） pentane with four products by monocholorination 9） pentane with only two products by dicholorination 18. Rank the following alkanes by boiling points from high to low: 1) octane, 2) methyl heptane, 3) 2,3-dimethyl pentane, 4) 2-methylhexane

Chapter 3 Orbitals and Bonding 1. Account for all the electrons in each of the following species, assuming sp3 hybridization of the second-row element in each case. Which electrons are found in sp3-hybridized orbitals? Which are found in σ bonds? (a) Ammonia (NH3) (e) Borohydride anion (BH4

−) (b) Water (H2O) (f) Amide anion (NH2

−) (c) Hydrogen fluoride (HF) (g) Methyl anion (CH3

−) (d) Ammonium ion (NH4

+) 2. Imagine describing the bonding in ammonia as arising by overlap of the half-filled unhybridized 2px, 2py, and 2pz orbitals of nitrogen with the half-filled 1s orbitals of three hydrogen atoms. (a) What kind of orbital would the unshared pair occupy?

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(b) What would you expect the bond angles to be? 3. Consider the species formed by the addition of an extra electron to H2 so that there are three electrons and a negative charge. Show an energy level diagram for this MOs of this species. Is there still a bond between the hydrogens-that is, is it still necessary to add energy tocause the atoms to separate/ Predict how the bond length of this species compares to that of H2.

4. Consider H2C=C=CH2. What is the hybridization and geometry at each C? Indicate the bond types for each of the carbon-carbon bonds. Draw the molecule, showing the overall geometry and the p orbitals that overlap to form the pi bonds. (The molecule is not planar.) Is it conjugate?

5. Explain the differences between the following data according to the hybridized orbital theory.

compound C—H bond Bond lengths/nmBond

energy/kJ.mol-1

CH3CH3 —C—H 0.110 410

CH2CH2 ＝C—H 0.108 422

CHCH ≡C—H 0.106 460

6. List the differences between C—C σ bond and C—C π bond？ 7. Write the hybridized states for C and N atoms in the following compounds and draw the

atomic array patterns in the molecules.

+NH4 CH3NH2 H2C＝O H2C＝NH H-C≡N

8. Designate the type of hybridization at hetero-atoms in the following compounds.

CH3OCH2CH2C N

N(CH3)2

CH3CO

A B

9. Explain why one of these carbocations is more stable than the other.

CH CH3 CH2 CH2

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Chapter 4 Proton transfer: A simple reaction 1. Write the relations between the conjugate acid and base and the relative strengths for acid and base for the hydrolysis of CH3COOH and CH3NH2, respectively.

2. Which is both acid and base in the following compounds?

NH3 NH4+ Br- HCO2

− HF 3. Rank the following species in order of increasing acidity. Explain your reasons for ordering them as you do.

NH3 H2SO4 CH3OH CH3COOH 4. Rank the following species in order of increasing basicity. Explain your reasons for ordering them as you do.

CH3O- H2O CH3COO- NaOH HF NH2

- HSO4-

5. The Ka of phenylacetic acid is 5.2 × 10-5, and the pKa of propionic acid is 4.87.

(a) Calculate the pKa of phenylacetic acid and the Ka of propionic acid. (b) Which of these is the stronger acid? Calculate how much stronger an acid it is. (c) Predict whether the following equilibrium will favor the reactants or the products.

6. Predict the products of the following acid–base reactions.

7. Methyllithium (CH3Li) is often used as a base in organic reactions. Predict the products of the following acid–base reaction.

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8. Label the reactants in these acid–base reactions as Lewis acids (electrophiles) or Lewis bases (nucleophiles). Use curved arrows to show the movement of electron pairs in the reactions.

9. As required, compare physical and chemical properties for each of the following groups

(1) CH3CH2OCH3 HOCH2CH2OH CH3CH2CH2OHA B C

(2) CH3O CH3NH CH3SA B C

(boiling point)

(basicity)

(3)OH OH

NO2

OH

CH3

A B C

(nucleophilicity)

(4)

CH3CCH3

O

A B C

CH3NO2 CH3COC2H5

O

(acidity of α-hydrogen)

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(5)

C C C CF3C F3C CF3

CF3H

H

H H

(A) (B) (boiling points and melting points)

(6)

CH3 CH2CH2 CH3CH2NH CH3C C CH3CH2 O(A) (B) (C) (D)

(basicity) (7)

CH2

CH3 CH3

(A) (B) (C)

(stability) (8)

O

NHCCH3O

O

CNHCH3O

O

A B C(nucleophilicity)

Chapter 5 Functional group and nomenclature I 1. Name the following organic compounds with IUPAC system

1)

2)

3)4)

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2. Name the following unsaturated hydrocarbons with IUPAC system

1） 2）

3） 4）

3. Name the following cyclic compounds with IUPAC system

1） 2） 3） 4）

5） 6） 7） 8）

4. Write a structural formula for each of the following compounds: (a) 6-Isopropyl-2,3-dimethylnonane (e) Cyclobutylcyclopentane (b) 4-tert-Butyl-3-methylheptane (f ) (2,2-Dimethylpropyl)cyclohexane (c) 4-Isobutyl-1,1-dimethylcyclohexane (g) Pentacosane (d) sec-Butylcycloheptane (h) 10-(1-methylpentyl)pentacosane 5. Hectane is the IUPAC name for the unbranched alkane that contains 100 carbon atoms. (a) How many σ bonds are there in hectane? (b) How many alkanes have names of the type x-methylhectane? (c) How many alkanes have names of the type 2,x-dimethylhectane?

6. Name the following aromatic compounds with IUPAC system

1） 2）

3） 4）

5） 6）

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7） 8）

7. Name the following organic compounds with systematic nomenclature

1）

2）

3）

4）

5） 6）

7）

8）

9） 10）

11）

12）

13） 14）

8. Name the following organic compounds with systematic nomenclature

1）

2）

3）

4）

5）

6）

7）

8）

14

9）

10）

11）

12）

9. Give the IUPAC name for each of the following compounds:

10. Which of the compounds in each of the following groups are isomers? (a) Butane, cyclobutane, isobutane, 2-methylbutane (b) Cyclopentane, neopentane, 2,2-dimethylpentane, 2,2,3-trimethylbutane (c) Cyclohexane, hexane, methylcyclopentane, 1,1,2-trimethylcyclopropane (d) Ethylcyclopropane, 1,1-dimethylcyclopropane, 1-cyclopropylpropane, cyclopentane (e) 4-Methyltetradecane, 2,3,4,5-tetramethyldecane, pentadecane, 4-cyclobutyldecane

Chapter 6 Stereochemistry 1. Write structural formulas for all the constitutionally isomeric compounds having the given molecular formula.

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2. Write the position isomers for the replacement of one hydrogen atom by chlorine atom in the following compounds.

3. Represent the chiral centers and the enantiomers using Fischer formula.

4. Do the following compounds have cis-trans isomers? If have, try to write them. 5. What enantiomers exist for the following compounds?

6. Identify the following compounds as identical, enantiomers, or diastereomers?

1) A

B

C

2) A

B

1) 2) 3)

1)

2) 3) 4)

1)

2)

3)

1)

2) 3)

4)

5)

6)

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3) A

B

4) A

B

5) A

B

6) A

B

C

7) A

B

C

7. Draw the stereo-structures for the following compounds.

1) (R)-3-methyl-1-pentyne 2) (S)-3-ethyl-1- hexene -5-yne

3) (2Z,4E)-2,4-hexadiene 4) (Z)-3-pentene-2-ol

5) (E)-4-methyl-3-isopropyl -3-hexene-1-yne

6) (2R,3S)-2,3- dimethylbutane 7) (2R,3S)-2-methyl-3-hydroxylpentanal 8. Name the following compounds by systematic nomenclature.

1)

2)

3)

4)

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5)

6)

7)

8)

9)

10)

9. Draw the perspective three-dimensional formulas for the following Newman projections, and

draw the Newman projections for the following perspective three-dimensional formulas.

1)

2)

3)

4)

10. Which compounds shown by the following Newman projections are enantiomers? Which are diastereomers? Which are different conformations for same compound?

1)

2)

3)

4)

11. Write the most stable conformations for the following compounds.

1)

2)

3)

4)

5)

6)

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12. Sight down the C-2±C-3 bond, and draw Newman projection formulas for the (a) Most stable conformation of 2,2-dimethylbutane (b) Two most stable conformations of 2-methylbutane (c) Two most stable conformations of 2,3-dimethylbutane 13. One of the staggered conformations of 2-methylbutane in Problem 3.17b is more stable than the other. Which one is more stable? Why? 14. Which do you expect to be the more stable conformation of cis-1,3-dimethylcyclobutane, A or B? Why?

15. Identify the more stable stereoisomer in each of the following pairs, and give the reason for your choice: (a) cis- or trans-1-Isopropyl-2-methylcyclohexane (b) cis- or trans-1-Isopropyl-3-methylcyclohexane (c) cis- or trans-1-Isopropyl-4-methylcyclohexane

16. One stereoisomer of 1,1,3,5-tetramethylcyclohexane is 15 kJ/mol (3.7 kcal/mol) less stable than the other. Indicate which isomer is the less stable, and identify the reason for its decreased stability. 17. (a) Write Newman projections for the gauche and anti conformations of 1,2-dichloroethane (ClCH2CH2Cl).

(b) The measured dipole moment of ClCH2CH2Cl is 1.12 D. Which one of the following statements about 1,2-dichloroethane is false?

(1) It may exist entirely in the anti conformation. (2) It may exist entirely in the gauche conformation. (3) It may exist as a mixture of anti and gauche conformations.

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18. Identify the following pairs of compounds as identical, enantiomers, diastereomers or structural isomers.

and

B

DCH3

H and

C

C=C=C C=C=CandCH3 CH3

CH3

CH3

Cl

ClH

H

H HH

H

ClH

CH3

BrH

A

and

CH3

ClHHBr

CHO

CHO

H

Cl

Cl

H

CHO OHHOH

CHO

H3C

19. Identify the following pairs of compounds as identical, enantiomers, diastereomers or

structural isomers.

Cl

Cl

H

H

H

ClCl

H

ClH

CH3

COOH

BrH

CH3

COOH

Cl HH Br

A

and and

B

CH3

HO

COOH

H CH3

OH

COOH

Hand

C

NO2

O2NNO2O2N

and

D

Chapter 7 Nucleophilic substitution reactions

1. Write the major products from the reactions of 1-bromobutane and the following compounds: 1） NaOH（aqueous solution） 2） KOH（alcoholic solution） 3） Mg，diethyl ether 4） product from 3) + D2O 5） NaI（acetone solution） 6） Na 7） CH3CO2Na 8） NaCN 9） AgNO3/C2H5OH

10) C2H5OH/NaOH

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2.Give the major products of the following reactions：

3. Compare the reactivity of the following compounds in each group: 1）Aqueous solution of NaOH： benzyl chloride, chlorobenzene, 1-chlorobutane 2）NaI in acetone solution 3-bromopropene, bromoethane, 1-bromobutane, 2-bromobutane

4. Describe the mechanism of the following reaction：

From which reactions can we get the isomeric products respectively？

5. Identify the following compounds using simple chemical testing methods: 1）3-bromo-2-petene, 4-bromo-2-pentene, 5-bromo -2-petene 2）1-chlorobutane, 1-bromobutane, 1-iodobutane

6. Upon treatment of a haloalkane possessing a formula of C6H13I with aqueous KOH solution product A is obtained. After A is reacted with ozone and then reductively hydrolyzed, (CH3)2CHCHO and CH3CHO are obtained. Please give the structure of the starting haloalkane.

7. Which of the following reagents can be used as a simple testing reagent to distinguish 1○, 2○

and 3○ alcohols? A. Sarret reagent (CrO3/Py/HCl) C. Lucas reagent (HCl/ZnCl2) B. Grignard reagent (RMgCl/Et2O) D. Jones reagent (CrO3/H2SO4)

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8. As required, compare chemical properties for each of the following groups:

(1) ClBr

BrBr

A B C D

Ph

(The SN1 reaction rate)

or

(Reaction rate)

(2) Br +

A

NH3CH3COCH3 Br +

B

NH3CH3OH

(3) H3C

HH

H

Br

Br

A B C

H3C

H HBr

BrH

H

H3C

H HBr

Br

(Reaction rate of the compounds with NaI)

(4) A

CH3CHCH3 CF3 CHCH3

B CCH3 OCHCH3

(Stability of the carbocations)

orBr +N

CH3OH

A

Br +N

CH3

B

C CH3

O

(Reaction rate)

(5)

(6)

Ph Ph Ph

(A) (B) (C) (stability of carbocations)

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9. Give major products of the following reactions, when necessary, show the stereochemistry of the products

(1)

OH HBr

(2)O HI

(3)

(4)CH2 Br

BrNaOEtEtOH

Chapter 8 Elimination reactions 1. Give major products of the following reactions, when necessary, show the stereochemistry of the products. (1)

(2)

(3)

(4)

O 1) CH3OH+CH2CH2S

_

2) H3O+

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ClC(CH3 ) 3

NaOEtEtOH(5)

(6) CH2=CHCH2CH2CH2OH Br2H2O

conc.H2SO4

(7)OH

HBr

2. When the following compound is treated with sodium methoxide in methanol, two climination products are possible. Explain why the deuterated product predominates by about a 7:1 ratio

3. Predict the products of E1 elimination of the following compounds. Label the major products.

4. As required, compare physical and chemical properties for each of the following groups

(1)

CH3

N(CH3)3H3C

CH3

N(CH3)3H3C

C(CH3)3

N(CH3)3H3C

A B C

(reaction rate of Hofmann elimination)

(2) H3C CH

CH2 O2N CH

CH2 CH

CH2

A B C(the reactivity towards the addition of HCl)

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5. When 1-bromomethylcyclohexene undergoes solvolysis in ethanol, three major products are formed. Give mechanisms to account for these three products.

6. Evidence has been reported in the chemical literature that the reaction proceeds by the E2 mechanism. Use curved arrow notation to represent the flow of electrons for this process.

7. Menthyl chloride and neomenthyl chloride have the structures shown. One of these stereoisomers undergoes elimination on treatment with sodium ethoxide in ethanol much more readily than the other. Which reacts faster, menthyl chloride or neomenthyl chloride? Why?

Menthyl chloride Neomenthyl chloride 8. The rate of the reaction is first-order in (CH3)3CCl and first-order in NaSCH2CH3. Give the symbol (E1 or E2) for the most reasonable mechanism, and use curved arrow notation to represent the flow of electrons.

9. In the acid-catalyzed dehydration of 2-methyl-1-propanol, what carbocation would be formed if a hydride shift accompanied cleavage of the carbon–oxygen bond in the alkyloxonium ion? What ion would be formed as a result of a methyl shift? Which pathway do you think will predominate, a hydride shift or a methyl shift? 10. Compound A (C4H10) gives two different monochlorides on photochemical chlorination. Treatment of either of these monochlorides with potassium tert-butoxide in dimethyl sulfoxide gives the same alkene B (C4H8) as the only product. What are the structures of compound A, the two monochlorides, and alkene B? 11. Compound A (C6H14) gives three different monochlorides on photochemical chlorination. One of these monochlorides is inert to E2 elimination. The other two monochlorides yield the same alkene B (C6H12) on being heated with potassium tert-butoxide in tert-butyl alcohol. Identify compound A, the three monochlorides, and alkene B.

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Chapter 9 Synthetic uses of substitution and elimination 1. Give major products of the following reactions, when necessary, show the stereochemistry of the products

(1)

CH3

H Br

CH2

HC CH2

+ Br2CCl4

(2)C C

CH3

Cl

Cl

H3C

H2/Ni

(3)HC CH2

+ HBrROOR

(4)

HH3CCH3COOH

OCH3OHH2SO4

CH3OHCH3ONa

(5) CF3CH CH2 + HCl

ClPh

H3C

+ H2OEtOH

(6)

(7)CH3CHCH

CH3

CH2

H3O

H2O

(8)

H5C2CH3

CO-S-Ph

HO NaOH

H2OO

(9)

H5C2CH3

COCPh

HO NaOH

H2O

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(10)

CH3CH2CH2CH2Br +CO

CO

NKNaOHH2O

(11)

CCCH3

H

H

H3C CH2I2

Zn(Cu) 2. Propose a rational mechanism that will account for the products of the following reactions.

OH

HCl

H NaOH (excess)(1)+

CH3

H

OH

HOH

H

CH3

H

H

OHH

CH3

H

HO

(2)CH2Br

EtOH

OEt

CH2OEt+ +

3. Synthesize the following compounds using the indicated reactants and other necessary reagents. (1)

From C CCH3

Br

H3C

Brto C C

CH3

H

H

H3C (2) OTs

CltoFrom

From(3) HC C H CH3CH2CCH3

Oto

(4)OH NH2From to

4. There are four compounds (A, B, C, D) in 4 test-tubes, please distinguish each compound by simple testing (6 points).

CH3 CHCCH3

OHCH3（ ）2 CH3 C

CH3

CH3

C CH

(A) (B) (C) (D)

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5. Synthesis of the following products from the indicated starting compounds and other necessary reagents.

(a)

CH3CH2C CHfrom to C COH

HHH3CH2C

HO

CH2 CH3

mesomer( )

(b)

from ( Ph )2CHCH2 CH2 OH to ( Ph )2CHCO

CH3

(c)

from COH

H3CCH2 CH3

CH2Br to C CH2OH

CH3H3CH2C

I

Chapter 10 Addition to carbon-carbon double and triple bonds 1. Write the major products derived from the reactions of 3-ethyl-2-pentene and the following reagents.

1) 2) 3) 4)

5) 6) 7)

2．Which compound has the highest activity towards electrophilic addition reactions?

1) A.

B.

C. D.

2) A.

B.

C.

D.

3) A. B.

C. D.

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3. Write the possible resonance structures of the following ions and point out the relative stability of them.

1)

2)

3)

4)

5)

4. Compare the thermodynamic stability of the following compounds.

1) 2) 3)

4) 5)

5. Differentiate the following compounds according to chemical techniques.

1)

2)

3)

4)

6. Synthetize the following compounds using HC≡CH as starting compound.

1) CH3C≡CCH2CH2C≡CH3

2)

3)

4)

5) (2R,3S)-2,3-bishydroxyethane 6)

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7. The formula of compound A is C5H8. Compound A can react with NaNH2 in liquid ammonia, and then the obtained solution is reacted with 1-bromobutane to form B (C8H14). Compound B could be oxidized by KMnO4 in acidic solution to generate two acids C and D with identical formula of C4H8O2. In the HgSO4/diluted H2SO4 solution, A is converted to E (C5H10O). Please give the structural formulas of compounds A to E, and the relative reactions according to the information described above. 8. Give major products of the following reactions, when necessary, show the stereochemistry of

the products (1)

ClCl

NaOHH2O

(2)

Me H

1) BH3/THF

2) H2O2/OH-

(3)

CH3

Br

NaOEtEtOH

(4)

H2OH2SO4,HgSO4

RC CH

(5)

1) O3

2) Zn, H2O

9. Compounds A, B, C and D possess the same formula of C6H12, Compound A can react with ozone. After basic hydrolysis of the intermediate acetone and propional are formed. By the same reactions compound D generate only one product. Compounds B and C do not react with ozone. The 1H NMR spectrum of B displays signals for CH3CH group, while the 1H NMR spectra of C and D both display only one signal. Please deduce the structural formulas of compounds A to D according to the information described above. 10. Deduce the molecular structures of compounds A, B, C and D according to the given reaction phenomena. Compound A, molecular formula C7H12, reacts with KMnO4 to give cyclohexanone; when A

30

is heated in acidic aqueous solution , B is formed, which can react with Br2 in CCl4 to afford C; D is yielded by heating C in EtONa/EtOH solution, butanedial (OHCCH2CH2CHO) and 2-oxopropanal ( CH3CCHO) are obtained when D is oxidized by O3 and then hydrolyzed in the presence of zinc dust; the oxidation of B by O3 and then hydrolysis in the presence of zinc dust gives 6-oxo-heptanal (CH3CCH2CH2CH2CH2CHO), please give the structures of A ~ D. 11. Synthesize the following compounds using the indicated reactions and other necessary reagents

(1) From PhCH2CH=CH2 to PhCH2

OCCH3

(2) From CH3C CH to rac- CH3C C CH3

H

HBr

Br

(3) From toCH3CHCH3

CHCH3

OHCH3CHCH CH2

CH2

CH3

(4) From toCH3

OH

Br CH3

OH

OC2H5

Chapter 11 Functional groups and nomenclature II 1. Write a molecular formula for each given name, for chiral compounds give three-dimensional

formulas (1) 1-propanol (the most stable Newman projection) (2) (2S, 3R)-1,3-dibromo-2-methylbutane (Fisher projection) (3) (1R, 3R)-1-tert-butyl-3-bromocyclohexane

(the most stable chair conformation) (4) 2-formylfuran (5) (1S,3S)–1-tert-butyl-3-bromocyclohexane (the most stable chair conformation) (6) 1-butanol (the most stable Newman projection) (7) (2R,3S)-1,3-dibromo-2-methylbutane (Fischer projection)

31

2. Give a systematic name of each of the following formulas. (1)

(2) (3)

COOC2H5

(4)

O

NH(CH3)

O

(5)

(6) (7)

(8)CH3

HH

H3C

(9)

HOC(CH3)3

COOH

COOHCN

CH(CH3 )2O

H2N

COOH

COOH

OH O

N(CH3)2

COO C2H5

32

3. Name the following organic compounds with systematic nomenclature

1） 2）

3） 4）

5）

6）

7）

8）

9）

10）

4. Name the following organic compounds with systematic nomenclature

1） 2）

3）

4）

5） 6）

7）

8）

9）

10）

5. Name the following organic compounds with systematic nomenclature

1）

2）

3）

4）

33

5） 6）

7）

8）

9）

10）

11）

12）

13）

14）

6. Write down the structural formulas for the following organic compounds

1） isoamyl acetate 2） 2,4,6-tri-tert-butylphenol

3） 2-amido-9,10-anthraquinone 4） α，γ-bismethyl-β-oxopentanoic acid

5） diphenyl carbamyl chloride 6） N-ethyl-1-(4-methylnaphthyl)methanamide

7） 3-chlorine-4-nitrobenzaldehyde 8） 2-amido-3-methoxylmonopropanoic acid 7. Give a systematic name for each of the following formulas or write a molecular formula for each given name.

(a) CH3HNCCH2CH2CNHCH3

O O

(b) CO

O CH2 CH3C

O

(c) N CH3 (d)

CH3

34

(e) (f)

H

H

CHCH3

C

O

H

C CH2CH3

CH3

CH

CH3

CH2 Give the name of the compound and the most stable Newman projection

Chapter 12 The chemistry of radicals 1. Give major products of the following reactions. (1)

BrBr2

hν, ROOR

(2)

+ HBr hvROOR

(3) 2. Synthesize the following compounds using the indicated reactions and other necessary reagents

Ph PhOH

from to (racemer)

3. What reaction do you suppose occurs when O2 is bubbled through a solution of the triphenylmethyl radical ? 4. The product of a Birch reaction is a 1,4-cyclohexadiene. Offer a reason why this product is not further reduced under the reaction conditions. 5. Show all of the steps in the mechanism for this reaction:

CH3

+ Br2hν CH2Br

+ BrH

CH3 C CH2

CH3+ CCl4 hv

35

Chapter 13 Bezene and Aromatic compounds 1. Designate whether each of the following molecules or ions would or would not be aromatic.

OS

N

A B C D

OH

N

HN

E F G H

2. Compare the stability of the following compounds.

A B C

3. Designate whether the following compounds are aromatic or anti-aromatic.

O O

N

N N

N

H(A) (B) (C) (D)

4. Derivatives of this compound have been found to have large dipole moments. Use resonance and the theory of aromaticity to explain this observation.

5. Coumarin is an important natural flavoring. Explain whether the oxygen-containing ring has any aromatic character.

O O:......

coumarin

36

Chapter 14 Aromatic substitution reaction 1. Complete the following reactions.

1）

2）

3）

4）

5）

6）

7）

8）

9）

10）

2. Distinguish the following compounds by chemical methods.

3. Synthesis the following compounds using benzene, toluene or naphthalene as main materials.

4. The formula of compound A is C9H8. The reaction of A and an equiv of Br2 under irradiation of light yield B and C, which possess a formula of C9H11Br。Compound B is optically inactive and C is also optically inactive, but C is a mixture of a pair of enantiomers. Phenyl group can be

37

predicted from the NMR spectrum of A. Write the structural formulas of A, B and C, giving the pair enantiomers of C in Fisher projection and designate R and S isomers.

5. Write the reaction mechanisms. 1). Write the products and mechanisms for the reaction of C6H5CH2CH2CH3 and Br2 catalyzed

by iron powder or under irradiation of light. 2)

6. Write the structural formulas for the reactants in the following reactions.

7. The formula of compound A is C9H8. It can react with the solution of Br2/CCl4 and with diluted KMnO4 solution at room temperature. Compound A absorbs 1 mol H2 at mild condition to yield compound B. The formula of B is C9H10. Compound A can react with 4 mol H2 under strong condition, and phthalic acid will be formed by the intensively oxidation of A. Try to write the structural formulas of A and B.

8. The formula of hydrocarbon A is C10H10, which can not reaction with CuCl/NH3. Compound B (C10H12O) is obtained from the reaction of A with dilute H2SO4. Intense absorption is found at about 1700 cm-1 in the IR spectra of B. Phthalic acid can be obtained by the oxidation of A. Write the structural formula of A and B as well as the reactions.

9. Compare the rate of nitration reaction for the following group.

NHCCH3

ONH2

A B C

10. Deduce the molecular structures according to the given reaction phenomena. Compound A (C11H12O2) can be obtained by the reaction of an aromatic aldehyde with acetone in dilute basic solution. Hydrogenation of A catalyzed by Pd/C affords compound B (C11H14O2). The reaction of A with I2/NaOH and sequential acidification gives CHI3 and compound C (C10H10O3). Both B and C can be oxidized by KMnO4/OH- to the same acid D (C8H8O3). Treatment of D with HI yields another acid E (C7H6O3). Intramolecular hydrogen-bond is formed in compound E. Please give the structures of A , B, C, D and E.

38

11. Give major products of the following reactions. (a)

+ (CH3)2C=CH2AlCl3

(b)

CH3

HNO3H2SO4

(c)

BrCF3

NaNH2

NH3 (d)

O2N CH3

HNO3H2SO4

(e)HF

(f)

NH2

BrBrOH

NH2

BrBrOH

NH2

BrBrOH

(g) CH3 Cl2

FeCl3 12. Show syntheses of the following compounds using the indicated starting materials and other

necessary reagents. (a)

CH2CH3

CN

(b)

NH2

Br

CH2CH2CH3

from to

39

(c) I

CH2CH3

Chapter 15 Additions to the carbonyl group 1. Which of the following compounds is formed by the reaction of an aldehyde or a ketone with a primary amine?

Urea (脲素) Amide (酰胺) Schiff base (西佛碱) Oxime (肟). A B C D

2. Predict the product of the reaction of propanal with each of the following: (a) Lithium aluminum hydride (b) Sodium borohydride (c) Hydrogen (nickel catalyst) (d) Methylmagnesium iodide, followed by dilute acid (e) Sodium acetylide, followed by dilute acid (f ) Phenyllithium, followed by dilute acid (g) Methanol containing dissolved hydrogen chloride (h) Ethylene glycol, p-toluenesulfonic acid, benzene (i) Aniline (C6H5NH2) (j) Dimethylamine, p-toluenesulfonic acid, benzene (k) Hydroxylamine (l) Hydrazine (m) Product of part (l) heated in triethylene glycol with sodium hydroxide (n) p-Nitrophenylhydrazine (o) Semicarbazide (p) Ethylidenetriphenylphosphorane (q) Sodium cyanide with addition of sulfuric acid (r) Chromic acid 3. Hydride reduction (with LiAlH4 or NaBH4) of each of the following ketones has been reported in the chemical literature and gives a mixture of two diastereomeric alcohols in each case. Give the structures or build molecular models of both alcohol products for each ketone. (a) (S)-3-Phenyl-2-butanone (b) 4-tert-Butylcyclohexanone (c) (d)

40

4. Choose which member in each of the following pairs reacts faster or has the more favorable equilibrium constant for reaction with the indicated reagent. Explain your reasoning. (a) Rate of reduction with sodium borohydride

(b) Equilibrium constant for hydration

(c) Acetone or 3,3-dimethyl-2-butanone (equilibrium constant for cyanohydrin formation) (d) Acetone or 3,3-dimethyl-2-butanone (rate of reduction with sodium borohydride) (e) CH2(OCH2CH3)2 or (CH3)2C(OCH2CH3)2 (rate of acid-catalyzed hydrolysis)

5. Each of the following reactions has been reported in the chemical literature and gives a single organic product in good yield. What is the principal product in each reaction?

41

6. Show the steps in the mechanism for this reaciton:

MgBr CH3CCH3

O1)

2) H2SO4, H2O

C CH3

CH2

Chapter 16 Substitutions at the carbonyl group 1. As required, compare the indicated property or reactivity of each group. (a)

NO2H3CCOO

CH3H3CCOO

H3CCOO

A B C

(the rate of saponification) (b) Which of the following compounds is the most reactive one towards an aqueous NaOH solution?

Cl CCH3

O

CHCH3

ClCCH2ClO

CH2C

O

Cl

A B C D (c)

(n-Bu)2CuLi (n-Bu)MgCl (n-Bu)Li A B C

(activity towards carbonyl groups)

2. Give the major products of the following reactions. (a)

CH3CHCH2CH2COOHNH2

(b)

CO

NH2Br2

NaOH (c)

COH

OHN3H2SO4

42

O(d) 1) 2 BuLi2) BrCH2Ph3) H3O

O

(e)

PhCH=CHCH2CNHCH3

O LiAlH4

H2/Ni

3. Syntheses of each of the following compounds have been reported in the chemical literature. Using the indicated starting material and any necessary organic or inorganic reagents, describe short sequences of reactions that would be appropriate for each transformation. (a) 1,1,5-Trimethylcyclononane from 5,5-dimethylcyclononanone (b)

from

(c)

from o-bromotoluene and 5-hexenal (d)

from 3-chloro-2-methylbenzaldehyde

4. Grignard reagent reacts with carbonate esters in a similar manner to their reactions with other esters. Predict the product of this reaction.

CH3CH2OCOCH2CH3

O1) excess PhMgBr

2) H3O+

5. Expain why one of these compounds forms a lactone when heated and the other does not. Show the structure of the lactone.

COOH

COOH

COOH

COOH

43

Chapter 17 Enolate and other carbon nucleophiles 1. As required, compare the indicated property or reactivity of each group. (a)

C2H5OCCH2COC2H5

O

CH3CH2CCH2CH3

O

CH3CCH2CCH3

OO O

A B C (tendency of enolization)

(b) CH2CH2CH2CCH3

O

CH2CH=CHCCH3

O

CH3CHCH2CCH3

O

CH2=CHCHCCH3

O

A B C D

(stability of carboanions) 2. The following three compounds are dissolved in one flask, please isolate each of the

compounds with simple chemical reactions.

H3CCO

O

H3C CC2H5 CH3CCH3

O

O A B C

3. Give the major products of the following reactions. (a)

ONH ,H 1)BrCH2Ph

2)H2O

(b)

O CHO + CH3NO2

NaOH

(c)

CH3COOEt CH3CHCHCOOC2H5

OH

C2H5

4. Show syntheses of the following compounds using the indicated starting materials and other necessary reagents. (a)

OCH2CH=CH2

44

(b)

CH3CH2C=CH2CH3C-OEtO CH3

5. Show all steps in the mechanism for the following reactions.

OOCH2=CHCCH3

OOO

CH2=CHCCH3

OOO

NaOH (excess)CH2=CHCCH3

O+

OO

6. There are 5 test-tubes. Each contains one of the following compounds. Please identify each of the following compounds using simple chemical testing methods.

CH3C-CHCH3

OHOCH3C-CH2CH3

OOCH3CPh PhC-CH2CH3

OCH3C-OCH3

O

A B C D E 7. In each of the following pairs of compounds, choose the one that has the greater enol content, and write the structure of its enol form:

8. Suggest a mechanism for this reaction.

OH OOH−

45

Chapter 18 Pericyclic reactions 1. Suggest a reasonable mechanism for the following reaction.

conc. H2SO4 +H OH

2. Give major products of the following reactions. (1)

O

O

+ 2CH2=CHCH=CH2

(2)

+ CH3CH=CHCHO

(3)

+ O

O

O

(4)

PhC-CHO + HCHOCH3

CH3

1) NaOH2) H3

+O

(5)

CH3CCH2CH3 + HSCH2CH2SHO Ni/H2

(6)

C=N

CH3O

OHH2SO4

(7)

CH3CH CCH3

CH3

CH3I

Ag+

46

(8) O

H

C2H5

CF3COOH

O

3. Show all steps in the mechanism for the following reactions. (a)

C NOHH3C

Ph

H2SO4

CH3CNHPh

O

(b)

OO

1) NaOH

2) H3OA EtOH

H2SO4B NaOEt

-EtOHC 1)NaOH

2)H ,D

COOH

4. Show all steps in the mechanism for this reaction.

CH3CCH3

O

CF3COOHO

CH3COCH3

OCF3COH

O++

5. Suggest a mechanism for this rection.

C C PhPhO

HH

BF3

room temperature 1 minute

C C HPh

H

Ph O

6. This reaction has been shown to occur in two thermally allowed steps. Show the structure of the intermediate in the reaction and explain why each step is allowed.

O

OCH3H3CO

C CH2

CH3 OH

OCH3H3CO

CH3CHCH=CH2

7. Suggest a mechanism fot this reaction.

H

H H

H

47

Chapter 19 Protective groups in organic synthesis 1. Synthesize the foolowing compounds with given starting materials.

(a) from to CCH2CH2CCH2CH2CH3

O

H

O

HOCH2CH2CH2C=CH2

CH2CH2CH3

CH3CCCH2CH2C CHO(b)

CH3CCH2CH2C CCOOHO

(c)

HCCH2C CH

O

HCCH2C CCOOH

O

2. Which of the following reagents can be used for the designated reduction?

CH3CCH2CH2CNH2

OO O ?CH3CCH2CH2CH2NH2

O O

3. Show a series of reactions that will accomplish these transformations. The use of protective groups is necessary. (a)

OCH3

OO

OH

O

(b)

HC CCH2CH2CH2CCH3

OCH3CH2-C CCH2CH2CH2CCH3

O

(c)

BrCH2CH2CH2CH2CCH3CH3

O CCH2CH2CH2CCH2CH3

O

(d)

OCOCH3

O OCH2OCCH3

O

(e) HOCH2C CH HOCH2C C-COOH

48

(f)

NH2

COOH

NH2

CNHCH2CH3

O

(g)

O

COOH

CH2

COH

O

Chapter 20 Carbohydrates

1. Give the major products from the reactions of D-(+)-glucose with following reagents:

1) hydroxyamine 2) phenylhydrozine

3) bromine water 4) nitric acid

5) periodic acid 6) acetic anhydride

7) benzoyl chloride/pyridine 8) methanol/HCl

9) methanol/HCl, and then (CH3)2SO4/NaOH

10) Treatment of the product from 9 with dilute HCl

11) Treatment of the product from 10 with strong oxidizing reagent.

12) H2/Ni

13) NaBH4 14) HCN,H2O/H+

2. Give the reason for the fact that the oxidation of 1,2-bonds in α-glucopyranose is faster than the

oxidation of those in β-glucopyranose by HIO3.

3. Please distinguish compounds in each group by simple testing methods:

(1) glucose and sucrose

(2) maltose and sucrose

(3) sucrose and starch

(4) starch and cellobiose

49

4. Designate which of the following carbohydrates are reductive sugars and which are non-reductive sugars? 1) D-mannose 2) D-arabinose 3) methyl-β-D-glucoside 4) starch 5) sucrose 6) cellobiose

5. Explain why methyl-α-D-glucoside does not exhibit Mutarotation in basic solution but in acidic solution.

6. The specific rotation of α-D-galactopyranose is +150.7°, and that of the β-anomer is +52.8°. The rotation of an equilibrium mixture of these two Anomers is +80.2°. Calculate the percentage of each in the equilibrium mixture.

7. Draw the chair conformation of β-D-allopyranose. Explain whether you expected this compound to be more or less stable than β-D-glucopyranose.

8. How is the product from the reduction of D-glucose with NaBH4 related to that from reduction of D-gulose?

9. The interconversion of α-D-glucopyranose and β-D-glucopyranose can occur in aqueous solution without passing through the open aldehyde form. Show a mechanism for this process. (Use acid catalysis)

10. Assign the configuration of each of the stereo-centers of these compounds as R or S. (a) D-galactose (b) D-ribose (c) L-xylose 11. Show a mechanism for the interconversion of D-allose and D-altrose in aqueous base. 12. Explain how the Kiliani synthesis could be used to demonstrate that naturally occurring glucose has the D-configuration; that is, that has the same relative configuration at C-5 as does D-glyceraldehyde at C-2. 13. A D-aldopentose, X, gives a product that rotates plane-polarized light on reaction with HNO3. Compound X can be prepared from aldotetrose Y by Kiliani-Fisher synthesis. Reaction of Y with HNO3 gives a product that rotates plane-polarized light. Show the structures of X and Y. 14. Synthesize the following compound from the give reactant.

CHO

CH2OH

H OHH OH

HO H

CHO

CH2OH

H OHHO Hfrom to

50

15. What aldohexose could be formed from D-galactose on treatment with base? Show a mechanism for the formation of this aldohexose. 16. Which of the following compounds undergoes mutarotation in basic solution?

OHO

H

H

CH3

H

OHOH

H

CH2OH

HOH

OH

OCH3

HOH

HOH

H

CH2OH

HOHO

H

H

OHOH

HOH

H

CH2OH

HOHO

H

H

COH

HOH

H

CH2OH

HOH

CH3H

A B C D

17. Please give the structures of A, B, C and D according to the described phenomena. (a) Carbohydrate A is a D-aldopentose. Compounds B and E both rotate plane-polarized

light, while F does not. Show the structures of A, B, C, D and E.

NaBH4

A

B

1) HCN2) H2O, NaOH3) HCl4) Na(Hg)

C + D

E F

HNO3HNO3

(b)

A C6H12 B C6H14

optically opticallyactive inactiveRisomer( )

C optically active D optically inactive

1

2

)

)

Hg(OAc)2/H2O

NaBH4/ NaOH

Chapter 21 Amino acids, peptides, and Proteins 1． Write the ionic structures of the following compounds in an aqueous solution with pH = 2.7−12: 1） Isoleucine 2）Aspartic acid 3）lysine

51

2． Predict the range of the isoelectric points for the following α-amino acid: (1) Alanine (2) Aspartic acid (3) Tyrosine (4) Cystine (5) Lysine 3．Please distinguish the following compounds using chemical methods: (1) cellobiose (2) starch (3) α-amino acid (5) β-amino acid 4. Show the four differently charged forms of histidine. 5. Why are the nitrogens in the side chain of glutamine and asparagines not very basic? 6. Explain why the form of arginine that has the side chain protonated is only a very weak acid (pKa = 12.5), even weaker than RNH3

+. 7. Explain which nitrogen of the side chain ring of histidine is protonated in the monocationic form. 8. Show a synthesis of Phe-Gly-Ala-Leu (a) by the solution phase method. (b) (b) by the solid phase method. 9. Write the major existing form of glycine (molecular formula: H2NCH2COOH) in aqueous solution at the following pH values.

pH = 2 pH = 6 pH = 11

10. Which of the following statement is correct? Proteins are naturally occurring polymers. The molecules of a particular protein________________________________________________________.

A. have the same molecular mass and contain the same number of amino acids connected in the same sequence.

B. have the same molecular mass but contain different numbers of amino acids connected in different sequences

C. have the same molecular mass and contain the same number of amino acids, which are connected in different sequences.

D. have different molecular mass and contain different numbers of amino acids connected in the same sequence.

11. An unknown pentapeptide is treated with Sanger’s reagent and then hydrolyzed with aqueous HCl to product Val, Gly, Leu, Ala, and Phe labeled with the dinitrophenyl group. After partial hydrolysis of the pentapeptide, three components were isolated from the complex reaction mixture.

52

Each of these components was hydrolyzed with aqueous HCl to give the following results: component 1 produced Val and Gly; component 2 produced Phe, Leu, and Ala; and component 3 produced Gly, and Leu. Deduce the structure of the pentapeptide. 12. Show syntheses of the following compounds using the indicated starting materials and other necessary reagents.

CH3CHCOOHCH3C-HO NH2

(racemer)