I CHTM. SOC DALTON TRANS. 1993

Synthes¡s and Characterisat¡on of Manganese(ttt)Unsymmetrical Schiff-base Complexes: a Unique Exampleof a Cocrystallised Manganese(ttt) Unsymmetrical Schiff-base Complex, and a Symmetric Schiff-base Complexarising f rom Rearrangement of the Formert

Ana Garc¡a-D6ib€,'Manuel R. Bermeio,r ' Antonio sousa," charl€s A. McAulif fe,róPaul McGlvnn,ó Peter T. NdifonD and Robin G. Pr¡tchard¿

r605

" Depattamento de Auim¡ca lnoryanica, Facultad de Auim¡ca. Un¡ve$idad deE 15706, Spainb Depadment ol Chem¡stty. Un¡veq¡ty of Manchestet lnst¡tute of Sc¡ence andM6O 1AD. UK

Sant¡ago de Compostela,

Tec h n ol og y. M a nc h e ste I

Some manganese(rrr) complexes with unsymmetrical Schifi bases have been p¡epared and characteisedThe ligands we¡e prepared by condensation of 7-amino-4 melhyl_b_ázahept-3'en-2 one wnhsalicylaldehvde,2 hydroxyacetophen one orsubst¡tuled sa licyla ldehydes (5 chloro.5-melhoxy,3 ethoxyo¡3,5'dibromo). On reaction with mansanese(I) perchlorate in ai, mansanese{rrr) Schiff'base complexesare obtáined. fhe crystal structures ol two of lhese have been determined. one being cocryfallised w¡lht{Mn(sálen)(H"O)}" l lC|OJ, containins the symmetr icál salen l isand [ /V, /v 'ethane-1.2-diy lb is-(salicyl¡deneiminate)1. Unlike lhe dimeric sructures previously found fo¡ similar complexes, the twosruclures are moñomeric with octahedml [4 n N,O. co -ord ination spheres.

It is well established th¿t manganese plays a ertnl role in somebiological syrems, e.s. in a superoxide dismut¿s ' and e ¿id.-insensitive catalasea I of grea1er import¿nce is that il is essentialÍor the oxidalion of watcr 1o 02 in the photosyntheticprocess,tr a h¿ving been found to be associated with the waleFoxidising comp¡ex in all O,-evolvirg pholosynlheiic organ¡msso far studied. Momver, ¡o oih.r melal has b€€n fou¡d toreaclivale lost O2 evolulion activily in reconstructed complexesdeficie¡t in manganes€-

There is curcntly a great deal of inierest in synthesisingmodels of this sysleñ based o¡ high-nucledily m¡ng¡nes€complexes, u¡:. Mn¡,5 Mn6ó ald Mns,? bul, mforlun¡tely. theabsenc€ oi water from rhee systeN inevilably render the¡tuseless as models for the water oxidisi¡g complex. although theynay have some validity as mod€ls for the post'wateFoxidisingcomplcx. we 3 and others e I a have exmined binuled systemsin an attempr to mimic the w¿1er photolysis action ofphotosyfem II of the gr€n plant. We have succeeded ingeneratiúg molcul¿r oxygen and r€ducing Ab€nzoquinone tohydroquinone by visible irradiation ofan aqueous elunon oftlMnG¿lpd)(H,o)],ltclo¿1,.2H,o ls¿lpd : rY,xrpropan€-1,3 diylbis{s¡licylideneininate)1. Re@ndy a quanlum-m@h-anical study or our work was publish€d by Awad and

We have sought to exlend our work to u¡symmetri@ltctradent¿le ligands bound 10 high-valenl rong¿nes. Althoughsuch ligands are rare they are ¡ot uknown and h¡ve b€encomplexed wilh oxovanadium(w),ró coppe(r¡). 1 I r3 nickel(rD re

We báve previously repored the synthesis of the un-symmetrical Schiü-b¿s ligand H,Lr from the reactio¡ of 7-amino-4-methyl-5-azahep!3+n-2"o¡e with slicylaldehyde(Scbeme l) and subsquently prepared the manganes€(r)

I Sutpl.h."totr .ltta aDailabk: w Instruclions for Aulhots, 1 Cr¿¿.5o... Dalton Trans.. 1993.lss@ I, pp. xxiii nviii.

(A;-

conplex t{Mnlr(Hzo)},ltclo4li 4Hzo.:o To our srearsurpr;s€ we found that, upon úradiationofan aqueoussolutionof ihis complex üth a tugslen la¡|)p for ó h. liSand re¿ú¿nge-ñenl o@ur¡ed and th€ manganese(ú) @nplex of thesymmetri@llis¿nd H,salen[{Mn(salenXHlo)}¿][cloJrH,o[salen : N,1v'-elhane-1,2'diylbis(salicylideneiminale)] wasisolal€d in .d. 40% ield; this re¿nanged complex wascharacierised by single-c¡/st¿l X-.ay techriques.'zo This isclearly a strange, and possibly iñporta¡t, obsen¿lion ¡nd wehave begun an invesligation of it. At li6t wc wish€d (o elablishthat ¿ r¿nge of unsymmetical SchilT'base complercs of ñan-s¿nes(ÍI) can be prepared and ielatod. These are reporedhere. We have also been ¿ble to obtain an X-ray cryst¿lstructure of a manganes(In) conplex of ar unsymmetricalSchiff base. as well as of a material which @nsists of acGryslallis€d ñansanee(In) conplcx cont¡ining synmetrical¿nd usymmetrical liga¡ds.

Results and DiscussionThe unsy¡nmetrical fthir-base liga¡ds @ listed in Table l.together wjth rH NMR data. Details of th€ir preparatiors andthose of their complexes are given in the Experimental section.All of the nang¡n€s€(n) Schir-base complexd h¿ve lhestoichionetry MnL(ClOa).rH1o, x : I 3 (Table 2).Ingeneralthe complo(es exhibit very simil¿¡ infr¿¡ed fe¡lures (Table 3) andthe lypical bards assigned to Schif-base ljgands are evident. Alshow a shift to lower en€rgy of th€ lisand v(GN) ba¡d onconplexaaion, dd a broad ¡bsorptjon cenlred at .¿. 3450 cm ',

.I. CHEM. SOC. DALTON TRANS 1993

T¡¡¡e I Anal¡icala.d'H NMR data for the ligards

Analysis(%)' tH NMR($)¡

H.L'

H,L"H,L'

CHN67 6(68.3) ?.6(?.1) I0.9 ( l1.4)68.4169.2) 7.s11.6) 10.100.8)64.5 (66.2) 7-3(1.6) 9.4(9.6)@3 (65.2) 1.3 (1.2) 9.2(10.1)58.1(59.9) 6.3 (6.1) 9.8(10.0).r0.1(4i .6) 3.7(4.0) ó.7(6.9)

H,

6.8 ?.56.9 ¡.956.8 ó.956.9 1.21.1,7.3

H6

4.95G)4.98G)4.92G)4.95G)

8.35(s) 1.710l.7t(1)

8.34(s) 3.?108.12G) 3.?(r)8.29G) 3.?(08.25G) 3.75()

3.ó(ñ) 1.9,2.0G)1.6(n) 1.9,2.0G)l.ó5(ml 1.9,2.0(s)3.(m) 1.9,2.0(t3.6(n) 1.9,2.qt3.65(ñ) L9,2.0(9

2.34(2J

3.8(s)

'Calcülaled valu6 in parenthes. ¡ Solldl CDrOD

T¡ble 2 AndlyLn¿land otherdar¿ for lhecomPle\es

[M¡L']CPrlH,o[M¡Ltr]CIo.H,oIMnLrlclo.2H:OIMnl-']cloa.2H:o[MrL']CIO4.2H?o[MnL']clo.Hzo

c17.5 (31_2)41.5 (4¡.8140.0(40.1)384(38.7)35.5 (35.r)29.t (29.2)

H4.6(4.8)4.5(4.8)4.915.0)4.5 (4.?)4.2 (4.0)2.5(2.8)

N6.216.2)6.4(6.515.ó(5.8)5 6 (6.0)5.4 (5.8)

5.04.884.8

0/K

16.6l5

,20.721.9

Cl Mn8.3(7.9)?.5(8.2) 12.1(12.8)1.911.4t 9.4 ( ! I .5)7.8 (?.6)

16.9(15- l ) r0.2111.?)

299313343329333451

' c¡lculal¿d valü6 i¡ pa..nlheÉs. ¡ Peaks coresponding 10 [M¡L]'

T¡bl€ 3 lnoo.l¡nl infÉred abso¡pdors (@ r) of the ligañds a complex6

H.L'[M¡L']Clo..lH,o

IMnL']clorH:o

tMnLrlclo.2HroH,L"[M¡L¿]C1or2Hro

IMnL:]clO!2H:o

[MnL']clodH¿o

v{o-H)

3450 (rbr)

3l50vs(vbt

!(cLH)2720vs

270ow (br)

2710v

21n*

{GN)l6l0s1625s

¡595sI629vsl6l8vsl6l5sl6l ls1639s

l6l0s

v(cr-o)

ll00Ys(vbr)

H"L]

H;1.

asicncd 1o acombin¿rion ofthev(O H) modes of co_ordiúateda¡d-l¿uice warcr. The broad uúsplit ¿bsorptions ¿t ú 1100cm I are irdic¿tive of xnco-ordi¡ated Perchloratc groups

¡rom mass spectral evidence (T¿ble 2) the structure of üe(omnlexc\ in lhe \o l iJ . t¿le h monomeric ralher lhan lhedrmirrc.r ,ucrures q< h¿ve prcviousl) lounJ for \ imi lar com'

¡lexcs. The FAB mass sfFtr¿ for all oflhese complcxes showcvidene fort¡eDrekncc oflhe ion [MnL]', ¡ ? ¿nonomcr'

Conclusileevidencc foi ihe mononeric struclure comcs froñihe sinslc-cryst¡l X ray aúalyÉs of [MnLtr(H,O),]Cloa'ElOH

and [MnLr(H1o),]ClO4 (s€e below). These are shown to benon;mers with octahedral MnN,O¿ co ordi¡alion sPheres.Allhoueh crvsral nor yel available lor lherefndin¡ns cmple\e(. rhe s imi lanly In the infrared and fABmass spectra and the magnetic suseptibility measureme¡tssuEsests that ihese too ¿re mo¡omers.

üas¡e¡ic measurements on these comPlexes reval rooñ-¡e. o"i" rur. .rsne¡

'" .o-enl\ clo\e ro 4 q.I ablc 2 con\isrent

w, lh a high-pin d" s)" leñ srrh no ñagcl ic inrer¿clronbersen the mangancs€ cerrre. . lhe magnclÉ beh¿\ iour hd'been ludied i¡ the lelnperarurc r¿nge 300 77 K. and in the caseot I Mnt " ICIO".2H,O in rhe rüt ¡ K mnCc. I ig l (¿randl l ¡ )zn¿ all co;Dkxes a ¿ tound toobev thecurie wehsla* Plor"of the r@iprocah of the mag¡etic susceptibililies á8ainr¿b"olure l . ;p.r¿rure arc l inear. sr lh Wei\s conran¡\ r¿ngingbetween 15 dd -28 K. Thes€ are indicative of vcry weak¿nliferrom¿gnelic jnter¡ctions.

Crcli. Vohatun¿¡ry Studi¿s. It is presumed that a¡ ,nter-mediale MnrnM¡rv tr¡rsilio¡ sl¿te is involvcd qhen w¿1cr ¡soxidised to oxygen in the ú¡tur¡l photosynrhcdc process ln the'model' systems which we hlve previously investigated it hasbeen sho;n úat the photoaclivity of 1be [{M¡L(H,O)},]':+complex (L = dianion of O,N, rctr¿dentate SchilT base) iscritic¡lly dep€nde¡t on the struclure of the lie¿nd. Thxs, in theprcrnr stud! c lc l ic volrammelq meu'uremenrs have beenqnie, l our In orde¡ to in\esr isdrerheelecrro(henisrry rnvol \ed

(H1

(H1

(H1

Ero

Br

(H3) (H1 fi1

H

H

HctBr

I

LE.

t o.io

J CHTM Sff DAI,TON IR^\S I99] t601

-1.2I

Fig. 2 Cyclic vollárnos¡ams fo¡2Il,o and (ó) [MnLlclo..H)o

2,0

the conple¡es (¿) [MrL¿]ClO1.

Clo. dnd i r . re¿,¡dn8ed nrudurr l tVnr\dtenf HrO,) . ' l [c to4]2rrom ¿ re.r l r¿xNarron ol [MnI lClO..1H.O from anhJ Jrou,Pr 'OH in da) l ight . Wh, l j l rh is ob\e^dt ion doe\ not shed t ishlor thc m{hanism of rhe ti8¿nd

'edr¿n8emenr do;..

nonerheles. o l ler conf imaf ion rh¿r al one norr l borh rhe(ompre\ \ontaining rhe un)mmerñ(at t igand anJ rhatconrarr ,ng rhc symmetr ical I ieanJ co-e\ i \ t

Cltstallogtuphic S¡!¿./¡¿s. F.om an elhanot solution of[MnL'(H,o)JClO4, ffystals suilable for X ray tudies wereobtaircd. The Strucrure oflhe cárion wirh the ¿t;m úuñocrms\cheme L rhosn in l ,g. L Arom,c.oordrnare\ ¡nd se¡e(re;bond leDgths and egles are givcn ir Tabtes 5 and 6 rcspccuve¡y.The moleculc consists ofa ñonome¡ic carion with rh; unsv;-merr ic¿l srhir l ba.e in rhe equdror i ¡ t pt¿ne dnd

'wo (ap;rn8

w¿rer molecules. completióg a disiorred-&laheor ¿rr¿nEe_menr T¡erei5 ¿ molecute ot erhanot in rhe la lue. r ron lhe.€ryslallistion slveúl. ¡nd ¿perch¡or¡te is the counte. ion.

f rom an ¡ .opropyl¿lcohol .otur,on ot IMn¡ (H.Or_l( tO¡.(^n¿ls \ur l ¡b le ,ór X rar \ ruJic, sere isot¿red Alomlcou¡din¿le\ and se¡e\1(J bond lengrh, and anglc, ¿re grten InTdb¡e' - anJ 8. Two drlTerenr mang¿ne5e (ompte\e\ arepre\ent: I vnL'r H/o)2]ClO¡, a monomer. imitdr ro rhccompound desc¡ibcd ¿bove. wirh lhe unsymmetic¿¡ ligard inthe equ¿lorial plane [N Mn N 84.?(8)"] a¡d rwoco-ordi¡atedwaters al Mn-O 2 30(2) A;n rhe api€al posilions ofa disrorted_ollahedral environnent of the metal (Fig.4)j a¡d rhect i l ro.ymñelrrcslen mang¿ne\e J imer | : Mniqten,, H.Ot: l .t ( ru4t ' . resuIrn8 trom the rear¿r8emcnr desc¡ ibcd berore ,One vlen o\)Ben. rn rdd ,on lo conrnbur ins to thc Schrf l -hd!(o N N-O squa¡e-plañ¡r arrangeme¡r óout uaogaoese,

i l05

u

ftK

Fie. I Plors or (¿l r il. ( ). 1- 1a) ¿nd (ó) I ú. tem¡calure ror rhecomplex [M¡L¡]CIO¿.2H,O

1.48 t . t7I l7t .5 l 1.250.21 0.41l.16 I 0.tl . t4 0.09LB 1.020. l5 -0.16| .52 l . l l ¡021 0.20

63:

00

T¡ble4 ElectrGhemical

[M¡LlClO¿¡HjO

IMnL)]ClOa.HrO

[MnLldO1.2H'O

lM¡LlctO1.2H:O

IMnL!]CIOa.2HrO

0l l

0.28

0.12

l .4 l

120

r08

l .46

tn lhe ¡cdox proce$ of thissuñnariscd in Table 4.

slale. The results a¡e

The voltmnoSrafns ofmor of thc complexes showed rwoo\ id¿r ion dni l two reducr¡on ne¿l\ . rndrúr ing rqo redo\p úc\r \ n,e\umabl) Vnrrr Mnu ¿nd Mnrt Vnrrr coupte.\one o I r hc com nle \e\ ,hos ed c.mplerel) re\ e^¡bte behd \ iour,burqLJ\ i - e\(^ ib leheha\ iourra\ iudged from rhepedt cu.enr

'¿lro. l t r¿\¡ ,bf^cdlr . 0. l l 0 l2V). fhepeak DusI.u ,¿r(

c lear l inUuened br rhe panrular t rgand prescnr. i or e\ampte.the half-wave potenli¿ls(¿.') olrhe most positive pair ofpeaksfor IVnL lc lo. . 'H:o i \ Bredrer rhan rhdr tor l i ' tnt

. l ¡ to. .2H.O{l 40comparedsi th 1.20V).asc(pecredirc, , ,c,q1runrcconsiderations. Unfortunatcly rhe solubilily of these complexes

'n co'nmon solvcnts was too low for oy meaningful coulo-

mer i ( \ rqdies. Whdt $c c¿n nroposc. hose\(r , F rh¿r rhe ¡edotproLe*e. intol \e Vnrrr Vnrrr ,ouptes. rhe tatrcrt { rnB ñu,e po. i r i \e and \howing qu¿j Fre, \ ib lc beh¿viou¡.Fig. 2(¿l ¿nd 2(r) .

\ 'abt l , t \ . , t rhc Coar l , \ct weh¿reprcv¡oú\t) ¡eponed rhe.ynr5e!J ol rhe complex [MnLi](1o". lH:O. Afrer i r ¡adia| lonol ¿1¿Llucou\ \o lur jon of i r wi th d ¡0OW runs\tcn lampforo h acompound was recovcrcd which X-r¿y studies rcvealed to bc ¿mansanese(m) comple¡ of the synñelric¿r schjfl_b¿se lisandsalen.:o We are atempling b study this rearargemcnt a¡dhave succeeded in bcins able to c@rystallisc [MnL1(H¡o)r]-

EN

1608 I CHEM SOC DALTON TRANS 1993

T¡bl€ 5 Posirional pa'ame1€rs ror [MnL](Hro):lclorElou

o( l )o12)o{8)o(r)q l2)N(2)N(5)c( l )c(l)c(4)c(6ic(7)c(8)c(s)c(10)

0.792 3( t)0.419 31.5)l . t305(8)0.7606(5)0.?9? l(5)0.?4?06)0.83? I (?)0.?98816)0.8240(8)0.89411)0.196919)

0.114 2t9)0.159 9( 1')0.?19( l )0.7884(8)

0.172 16(6)0.112l( l )0.421 5(4)0.5270{3)0.152 l ( l )0.lt0 t(3)0.2r43(4)03808(4)0.r35 8(5)0. ¡94 r(s)0 269 4(5)0.4?18(J)0.5?8 41t0.6027(5)0.717l(6)0.1502(5)

o..roruorrl0.114 5(l)0.177 t(:l)0.4r04(2)0.412 q2J0.ó600(3)0.21) 4t3)0 209 0(3)0.3093(5)0.1ó7 4(4)0 r2J 5(4)0.t85 9(4)0.2ó5 5(5)0.3670(5)0.,140 40)0.4115(4)

c(r¡)c(r2)c(13)c(14)c(r 5)c(r6)c(r 7)c(r8)o{20)c(21)c'l22)clo(3)o(4)o(5)o(ó)

i.r, o,r,0.755 5(8)0.742\t)0.752(r)0.775(¡)0.714 6(.9)0.r21(l)0.?15( l )0.359 7(6)0.120( I)0.1r4( r)0.222 514)0.l9,l(l)0.238( l )0 071( l )0.1?8(l)

0.2565(5)0.2615(5)0.168 s(6)0.0621(7)0.0531(ó)04643(5)0 385 20)0 50? t(8)0.r 3r 9(4)0.015 2(7)0.015(8)0. r99 5(2)0. r016(4)0. r62 06)0.26460)0.265 8(6)

0.488 8(4)0.590 41,1)0.6¡47(6)0.5194{6)0.4395(6)0.07ó9(4)0.7661(5)0.822 8(6)0.r34 3(t)0.r r8 7(ó)0 2l l7(7)0.09? 9(l )00?21(4)0 2007(5)0.07¡J9(5)

-o.M6 2(7)

tMnLlHjO)j '

M¡ o( l )Mn o(2)Mn o(8)

o(lFMn o(2)o( lFMno(l l )o( lFM¡ N(2)

interaroric dislances (A) aod ánsles (') for

2 265(4)1.420(6)1.89?(3)

1?5.?{2)90.9(2)88.4(2)

Mn o( l l )Mn N(2)Mn N(5)

t.874(4)1.970(5)1.954(4)

o(8FMn o(ll) 91.6(2)N12FM¡ N(5) 83.8(2)

Fig. 3 Slruclu¡eof thecalio¡ [M¡L'(H'OL]'. inclüdingthclabclli.g

Mn-O 1.87(l) A, c¡ps a wo¡d mansanese, Mn o 2.36(l) A,opposite an apical water nolecule. M¡ O 2.22( l ) A. The crysral. r rucrure r \ com¡leled b) perchlor¿re an,on\ ¿rd PrrOH ofcrystallisation, which lake parl in a complex hydrogeú'bo¡dingshene with alternating monomer a¡d dimers linked i¡toin l in i re,h¿in. b) O. . O sep¡r¿non. ¡anging i rom 2.7 l r5) ro2 94(3) A. s.e Fig. 5.

Exp€rim€rt¡lI.isand Prcparction. The nelhod of preparatio¡ of the

u¡symneftical Schiff-bas liga¡ds is a modificatio¡ of themethod of Cosres re ¡¡d is illustrated below.

To the amine 7'mino-4'methyl 5-dahept-3 e¡-2-onc I ( l0 g,7.0 x l0: nol) in absolute ethanol (20 cmr) was add€d thesubstiluted salicylaldehyde (7.0 x l0' úol) or 2-hydroxy-acelophenone. Therrixture war srirreda¡d heated 10 40"C for10 nin. cooled to room temperatu.e, and concentrated underv¿cuun, wher€ a yellow solid of the unsymmelric¿l Schir bas.tlzl-, precipit¿led. This was fillcred oll, washcd wirh eth¡nol

Fi& 4 sr¡üdure of rhe c¿tion IMn Lr( H jo)J '- inclüding rhe láb€lli¡s

(2 x 20 cñr), and dried under vacuum at room temperature.The yi€lds were almost quantitative. Aralytical a¡d 'H NMRdata are given in Table 1

Cóhplet Prcparation. All the ma¡ganese( ) Schiff'basecomplexes were prepared in an idenlic¿l manncr, employing amodified melhod oriSi¡ally developed by Boucher a¡d Coe.?rThe geneElmclhod is outlined below.

To the lisard H,L (5 mmol). dissolved in ethanol nethanol(l:1.75 cmr). was added MnClOa.dH,O (5 úmol). No reaclionappeared to o@ur until the additio¡ of an aqueous solul'on(2 cmr) of NaOH (10 mmol), ¿fte. which rhe solurionprogressively d¿rkened. After rirring in the presen@ ofdust-frcc air for about 5 d a bl¡ckish precipitale oiúanganese oxidesand sone other side prodxcts was fllered olT aDd rejeled. Theiolut ion $as lef l dr room remprralu¡e Lnr i l c \aporat 'onrcsulted in a brown precipitáteoflhe complex. Thiswas washedüth clld ethanol (25 cmr) ¿nd dry diethylethe¡ (2 x 25 cm3),a¡d dried in vacuun. Yields .o. ó0%. Tbe cr/st¡ls of[MnL](HzOtlClOa.ElOH were oblaired after re.ryral-lisalion from ethanol.

?hlsi.al Meaercüen1s. Elmenlal analy$s wcrc pc¡fomcdby the Elemental A¡allsis Services ofthe Insdlute and by theUúiversily of Santiago. Infrared spectra were recorded on aPerki¡ Elner | 80 spectrophoromeler. Magnetic susceptibililies*erc ne6ured in the rangc 100 70K by use of a Faradaybalane. usrng d f ie ld oI .0O0 C ru.5 l )¿nd in oncc¡se usinga

J CHEM S(T. DALTON TRANS. 1993 1609

Tlble 7 Posnional p¿¡ameteñ ro¡ [MnL \ H:o),]cto¡ and o.5t1M.G¿len)(H,oN:ltcto.ltr with pr,oH e¡venr

Mn(l)q¡)o(21o(3)o(4)N(2)N(5)c( 1)c(3)c(.1)c(6)c(?)c(8)c(9ic(10)c( l l )c(r 2)c(r tc(14)c(r5)c(r6)cr(t)ql l )o( r4)o(t5)o( l6)

c(4r)c{12)

i.,,rnn,0. r l4( l)0.02?(r)0.113(r)0.232{¡)o.2541.2)0.166(2)0. r90(2)o 391(l)0.440(l)0.4r{2)0.341(2)0 2| l (2)0.11J( l )0.059(2)

-0.025(2)0.15?(3)0.20?o)

-0. t : l l (3)0.00 ro)0.55713)0.548r(8)o.482(.210..rór(2)0.ó08(3)0.626(4)0.216\2)0 30r( l )0.417(3)

0..t7660)0 4561t )0.1?8{r)0 6n0( l)0 1.14( t)0.50ó(r )0.5?3i l )0.48f2)0.564(2)0.612(2)0.586(2)0.5r3(2)0471(2)041q2)0.428(2)0176(2)0.3r7(2)0.31412)0.158(2)o.42q2)0.656(2)0.1845(7)0.ró8(2)0.318i2)0.33{2)0.485(2)0.809(l)0.841(2)0.834(l)

0.6265(1)0.46t( I )

0.64ó(r )0 6I ] ( r )0.7981¡)0.67t12j0.852(2)0.865(2)0.?94O)0.60(2)0.48(2)0.416(2)0.282(2)0.199(2)0.6?l(2)0.624(3)0.t00(l)0.8r9o)0.869(2)0.14(1)0.7854{8)o.6|(.2J0.829(2)0.805(3)0818( l )0.?89(2)0.9r0(l)0.998(l)

c(43)Mn(2)o(5)o(6)o(7)N(221N(2tc{21)c(23)c(24)c(26)c(21Jq28)c(29)c(30)c(3r)c(32)c69c(34)c(ltc(36)c(37)c(18)c(2)o(2r)ol22)o(21)o(24)

o.rrrtal0.06ó4(4)0.072(r)0.033(r)0091(D0.r 84{2)0.221(2j0.r59(2)0 3r8( l )0.133(2)0.234{l)0.03r(2)o.o71(2)0.203(2)

-0.2r0(2)0.101{:l)0.0l f l )0.121(2)0.003(2)0.09:t(l)0.05913)0.07u)0.r 6(2)0.5600)0.504(6)0.4?l(4)0.656\4)0.610(l)

o rrqrl0.929(3)0.¡Jt0(l)0.936(r)0.808(l)o_941í.D1.014( t)0.910(2)r .0r l (2)| 09?1.2)l.054{2)0.845(2)0 rJ06(2)0.136t.2)0.107t.2)0.743(.2)0.809(2)0.998(210.942(2)0 892(2)0.90f2)0.968(2)r .0r5(2)0.93J( l )0.939(4)0.867t.2)0.92r(3)1.036(2)

o.qrt,l0.4946(3)0.351(r)0 56 r( l )0.568(r)0.432(2)0615(2)0.127(2)0.523(2)0_622(2)o.14t(2)0.235(2)0.243(2)0.l4ó{2)003q2)0_020(2)0.r r9(3)0.16J(2)0.6?f2)0.708(2)0.826(3)0.9r5(2)0.887(2)0.?.1ó(l )0.806(t0.641(l)0.19715J0.149t.4)

T¡ble I sclsled inr€ntomic d¡ranc6 (A) a¡d ans¡6 f) forfM¡L1H2O)' l ' and t lMnGalenXH'Or?tr .

M¡(rrc(t)Mn(lFO(:¿)Mn(lF(l)Mn(1rc(4)Mn(lFN(2)M¡( l ) Nl5)

o( l ) Mn(t)¡ l (2)o(l fM¡(r) o( l )( ) ( lFMn(1) O14)o(r) Mn(r) N(2)o(rFMn(r)-N(5)o(2) Mn(lI¡Ol

Mn(2H)(5)Mn(2p(6)Mn(2)O(6)Mn(2rc(7iM¡(2FN(22)Mn(2)-N{2t

SQUID SHE magnetomerer in the range 300 2K. Cycticvollañmelry was perfomed o¡ ¡ EG and c PriDccto¡ AppliedReseafch Co.p. Modcl 362 potenliofat in conjunction with alhre'electrode cellfitted with a purge-gas inlet ¡nd outlet aDdco¡sislinS of a plati¡uñ-wi.c r¡rking e¡elrode, Ag AgCl.efercnce e¡eclrode ¿nd aplalinu¡¡ ¿uxiljary elecrrode, usinaaúac€lon'lrile solution of the m€rallic complexes cont¿ining 0.2mol Jm rer¡aerh) lmmonrum pe'chlor¿re d. supponrnBelecl.olyte. Thc FAB mas spetra were .eorded on a Kr¡tosMS5oTC spcctromeler connected toaDS 90d¿tasysteñ. usingn nitrobenz]'l alcoholas solvenr.

Crystollostdthtu Measúemerh. For the crystals of IMnL],(HtrO),lClO4 measuremcnts were nade on an Enr¿f-Nonius CAD-4 diflr¡ctometer. wirh monochromated Mo-Krr¿diarion 1), = 071069 A) usins e26 scans. Structu.e(aLular ion. qere pclomed by J i rccr methodr ujnBVITHRIL:: ¿nd l t l pdramereb qere r(hncd by fu l t -ndrr i ;le¿rr \qudrc.s i rh I f \SqN: ' roahn¿lR - 0.064.,R - 0.031..= l [o14)+o.o]r . . ' l .

All non'hldrogen atoms *ere refined anhotopic¿tly andhydrogcn atoms consÚ¿incd lo chemicallv reasonable posirjons.Of thc 374J reflections collered. 1689 N€rc u¡ique 1n$, :

O*

-/¿\:L

F¡g,5 Cryst¿l rrüduE of ibe cüryrallised tMnL'(H:O)rlC¡Oa a¡d'rs

rsnansed producr [{ Mn(s¡leú)(H2o) },']fcloatz

0 0l . l ) and 2r l4 (onsidered d. obsc^ed l . > . ¡o, n l . R.\ idualelecrron densit) in rhe linaldifferencr map ranped trom 0.:t0Lo065cA r

,..1:t!t:t- tut! /¿f tMnL¡(H,o),lClo1.EtoH, _C1sH30-(- lMnN)O,0. Y - 5r4.EJ. Incl in( . space group rT rno. i ; .o - . t - t3t . b . t27óo,)r . , - I l .q45rbr. ; - ¡ . t5( t .p =92.88(3). ] : 95.78(3)". u = 1119(2) 4,. z = 2, D. =1..{?8 gcm tr. É(Mo-Kd) : 7.03 cnj, ¡(000) = 548.

I¡ the @se of the crystal with two different mansanesccomp¡exes the measurements were made oñ a Rjs¿ku AFC6Sdi ' l rdcromeler s i th monochromared Mo-K, r¿¡ i¿f ion t^ -0 710 60 A) usng o .¿0 sqni . A roldt of b958 rcf le on\

"ercrecorded ofwhicb 1476 were coisidered obse.ved U > 2o(tl

t .9t(2)l 89(2)2.10(2)2.10(2)r 97(2)r .9(2)

e2.9(7)9l.l(6)89.4(6)

116.817)93.0(8)rJó.?{6)

1.37(r)r.87(r)2.3ó1r)2 22l.tJl.96(2)| 94(2)

c\2FM¡(rrc(4) 88.0(6)N(2FMn(tl N(5) 84.7(8)o(sFMn(2FO(ó) 95.2(6)o(5FMn(2FO(?) 92.1(6)o6FMn(2FN(22) 90 u(7)N(22FMn(2FN(25) 82.9(8)

l6 l0

Residuat density in thc final Fourier dirsence maps rangcdfr.m 041 ro u4) €A t Smcrurc calculatio¡' $ereperformcd by dir€c1 metbods üsi¡8 MITHRILzz and reñned byfull-matrix leasl squares with TEXSANTT to a ñnaln - 0.075,n': 0.081. r = l / to'(4) + 0.1¡'1.

Ctrsldt ¡Idt¿. [MnL¡(H2o)?]Cloa+0.5tlMnG¿len)-(H,Or:ltclo4l, + PÍ'OH solvenl. _Ca3H4aCl,Mn,NaO16.M : 933.51, iriclinic. space group Pl (¡o.2), o = 13.26(2),¡=15.01(2). .= 13.00( l ) A, ü=95.2( l ) . 0= 113.45(8),/=115l(r f , u 2oJ1\\{ ' , .2- 2. D - Lr258cm\.r(Mo-Kd) : 7.98 cm r, f(000) = 9ó8.

Addilional malerial for both complexes av¿ilable from thec¿mbridge Crylallographic Data centrc comprises H-alomcoordinates. themal parameters and rcn¿ining bond lenglhs

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Recetuetl24th Aususl 1992a Pap.r 2104563J