Separation of Ferrocene and Acetylferrocene

Experimental Organic Chemistry

Experimental Center for Chemical

Education in Fudan University

Objectives

1. Learn the principles of thin layer chromatography and column

chromatography

2. Separation of ferrocene and acetylferrocene

3. Learn and master techniques of the pressurized flash column

chromatography

Background

For organic synthesis, the mixture is often acquired, which

might include substrates, products, catalysts, by-products. In

order to get the single and pure compound, further

purification is necessary.

It was known that many different methods have been

developed for purification. This experiment is to learn one of

the most general measures in organic laboratories. It is the

adsorption column chromatography, which is suitable for the

separation of solid-solid, liquid-liquid, solid-liquid mixtures.

Principles

1. Adsorption column chromatography and Thin-layer

chromatography (TLC) : separation is achieved by using the

different adsorption and desorption capacities of the components in

the mixture in the insoluble two phases (i.e. the mobile phase and

the stationary phase)

2. The mixture of ferrocene and acetylferrocene is mainly isolated

by utilizing the difference in adsorption capacity of silica gel.

Nouns

1. Stationary Phase and Mobile Phase (Adsorbent and Eluent)

2. Rf Value

3. Column Chromatography

4. Thin Layer Chromatography

adsorbent

Experimental Medicines

The mixture of Acetylferrocene and Ferrocene

Acetylferrocene (FW 228.07, mp 81-86℃)

Ferrocene (FW 186.04, mp 173-176℃)

Petroleum Ether (PE) (rectification, boiling range 60-90℃)

Ethyl Acetate (EA)（FW 88.11, bp 77℃）

Silica Gel (300 - 400 meshe)

Quartz Sand

Content - Thin Layer Chromatography

1. Draw the starting line, which is about 0.5 cm

from the bottom of the silicone plate

2. Mark three points on the starting line with

a pencil and write down the mixture, ferrocene,

and acetylferrocene.

3. Use the capillary to transfer the corresponding

sample to the point.

4. The plates are placed in different polar

developing agents. Record Rf values after

running.

the silicone plate point sample run

Objectives: 1. To analyze constituents of the

mixture.

2. To determine the polarity of

eluent in column chromatography

Content – Column Chromatography

Atmospheric column

chromatography unit

Pressurized column

chromatography unit

Content – Column Chromatography

Packing column:

1. 15 g Silica gel and 60 mL PE are placed in a 100 ml beaker, and sitred evenly.

2. Add 10 mL PE to the fixed column, and keep it dripping naturally.

3. Transfer the suspension PE and silica gel to the column. Compact the stationar.

phase, and ensure that there are no bubbles in the column.

4. Add 1-2 mm quartz sand on the surface of silica gel.

Add sample:

A 1 mL sample is evenly dropped onto the surface of the quartz sand and allow the

crude product to adhere to the silica gel under light pressure with the assistance of

the eluent PE.

Elution:

Under the conditions of pressurized elution, the PE/EA (10/1) eluent is used

firstly. After the first compound (ribbon) is completely eluted, PE/EA (2/1)

eluent is used. Each compound is collected in a separate conical flask.

Packing column：Wet packing technology is selected in this experiment

Elution：Pressurized rapid elution is selected in this experiment

Notes

1. During the packing process, it is required that the stationary phase is

uniform and there are no bubbles inside, otherwise the separation efficiency

will be affected.

2. The stationary phase is soaked by the eluent without cracking, otherwise

the separation efficiency will be affected。

3. Before loading the sample, a small amount of quartz sand is added on the

surface of silica gel to avoid smashing the stationary phase when dropping

the sample. 4. Weigh the silica gel in a fume cupboard to prevent silica gel from inhaling

into the nasal cavity. 5. During the elution process, the eluent should be poured slowly to avoid

smashing the stationary phase.

6. During the elution process, ensuring the appropriate pressure and flow rate

of the eluent are critical.