A MECHANISM FOR THE REARRANGEMENT OF UNSYMMETRICAL TETRADENTATE (N2O2) LIGANDS BOUND TO MANGANESE(III) - THE ISOLATION AND CRYSTAL-STRUCTURE OF A MANGANESE(III) COMPLEX CONTAINING A 10-MEMBERED CIS-CHELATED RING

被引:24
作者
BERMEJO, MR
DEIBE, AG
REY, M
SANMARTIN, J
SOUSA, A
AURANGZEB, N
HULME, CE
MCAULIFFE, CA
PRITCHARD, RG
WATKINSON, M
HELLIWELL, M
机构
[1] UNIV MANCHESTER,INST SCI & TECHNOL,DEPT CHEM,MANCHESTER M60 1QD,LANCS,ENGLAND
[2] UNIV MANCHESTER,DEPT CHEM,MANCHESTER M13 9PL,LANCS,ENGLAND
来源
JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS | 1994年 / 08期
关键词
D O I
10.1039/dt9940001265
中图分类号
O61 [无机化学];
学科分类号
070301 ; 081704 ;
摘要
The unsymmetrical Schiff-base ligand L1 (where H2L1 is the condensation product of 8-amino-4-methyl-5-azaoct-3-en-2-one and 3-ethoxysalicylaldehyde) has been found to rearrange into the symmetrical ligand L2 [H2L2 = N,N'-bis(3-ethoxysalicylidene)propane-1,3-diamine] in the presence of manganese(III). The manganese(III) complexes of both the unsymmetrical and symmetrical ligands have been characterised by elemental analyses, infrared spectroscopy, magnetic susceptibility measurements and fast atom bombardment (FAB) mass spectrometry and have been assigned the stoichiometries [Mn(HL1)2][ClO4].H2O and (MnL2][ClO4].3H2O based on these data. The FAB mass spectrum of the former exhibits an interesting phenomenon, with two distinct metal co-ordination environments being observed. The ion of [Mn(HL1)2]+ at m/z 661 is observed, as would be expected from the experimental data; however, the parent ion peak at m/z 357 corresponds to the monomeric [ML1]+ ion with the amine nitrogen atom of the ligand deprotonated. The manganese(III) complex of the unsymmetrical ligand [Mn(HL1)2][ClO4] has been crystallographically characterised, no water of crystallisation being observed in the selected crystal. This monomeric complex consists of a pseudo-octahedral metal centre with an N2O4 donor environment. The non-co-ordination of the amine nitrogen atom, confirmed by the Mn ... N(2) separation of 3.51 angstrom, produces a ten-membered chelate ring about the manganese ion, believed to be the first example of such a system. The crystal structure has enabled a mechanism for the rearrangement of Schiff bases about manganese(III) to be proposed. It involves a series of reversible hydrolysis reactions which are stabilised by manganese(III) acting as a template.
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页码:1265 / 1269
页数:5
相关论文
共 21 条
[1]   METAL(III) COMPOUNDS OF POTENTIALLY SEPTADENTATE [N4O3] LIGANDS .2. CRYSTAL AND MOLECULAR-STRUCTURES OF [M(C27H24CL3N4O3)].3H2O(M=CR,MN) [J].
ALCOCK, NW ;
COOK, DF ;
MCKENZIE, ED ;
WORTHINGTON, JM .
INORGANICA CHIMICA ACTA-ARTICLES, 1980, 38 (01) :107-112
[2]   A NOVEL MANGANESE(III) DIMER WITH AN EXTREMELY LONG MN-MN DISTANCE [J].
ASHMAWY, FM ;
BEAGLEY, B ;
MCAULIFFE, CA ;
PARISH, RVD ;
PRITCHARD, RG .
JOURNAL OF THE CHEMICAL SOCIETY-CHEMICAL COMMUNICATIONS, 1990, (13) :936-937
[3]   WATER PHOTOLYSIS .1. THE PHOTOLYSIS OF COORDINATED WATER IN [(MNL-(H2O))2][CLO4]2 (L = DIANION OF TETRADENTATE O2N2-DONOR SCHIFF-BASES) - A MODEL FOR THE MANGANESE SITE IN PHOTOSYSTEM-II OF GREEN PLANT PHOTOSYNTHESIS [J].
ASHMAWY, FM ;
MCAULIFFE, CA ;
PARISH, RV ;
TAMES, J .
JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, 1985, (07) :1391-1397
[4]   3-AMINO-1-PROPYLAMMONIUM PERCHLORATE - AN EXTENSIVELY HYDROGEN-BONDED SYSTEM [J].
AURANGZEB, N ;
MCAULIFFE, CA ;
PRITCHARD, RG ;
WATKINSON, M ;
GARCIADEIBE, A ;
SOUSA, A ;
BERMEJO, MR .
ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS, 1993, 49 :1656-1657
[5]   STRUCTURALLY DIVERSE MANGANESE(III) SCHIFF-BASE COMPLEXES - CHAINS, DIMERS, AND CAGES [J].
BONADIES, JA ;
KIRK, ML ;
LAH, MS ;
KESSISSOGLOU, DP ;
HATFIELD, WE ;
PECORARO, VL .
INORGANIC CHEMISTRY, 1989, 28 (11) :2037-2044
[6]   SOLAR-ENERGY BY PHOTOSYNTHESIS [J].
CALVIN, M .
SCIENCE, 1974, 184 (4134) :375-381
[7]   2 MANGANESE(IV) COMPLEXES WITH ISOMERIC MNN4O2 SPHERES INCORPORATING HEXADENTATE AMIDE AMINE PHENOLATE COORDINATION [J].
CHANDRA, SK ;
CHAKRAVORTY, A .
INORGANIC CHEMISTRY, 1992, 31 (05) :760-765
[8]   MANGANESE CARBOXYLATE CHEMISTRY AND ITS BIOLOGICAL RELEVANCE [J].
CHRISTOU, G .
ACCOUNTS OF CHEMICAL RESEARCH, 1989, 22 (09) :328-335
[9]   MONONUCLEAR MANGANESE(IV) IN TRIDENTATE ONO COORDINATION - SYNTHESIS, STRUCTURE, AND REDOX REGULATION VIA OXYGEN DONOR VARIATION [J].
DUTTA, S ;
BASU, P ;
CHAKRAVORTY, A .
INORGANIC CHEMISTRY, 1991, 30 (21) :4031-4037
[10]   SYNTHESIS AND CHARACTERIZATION OF MANGANESE(III) UNSYMMETRICAL SCHIFF-BASE COMPLEXES - A UNIQUE EXAMPLE OF A COCRYSTALLISED MANGANESE(III) UNSYMMETRICAL SCHIFF-BASE COMPLEX, AND A SYMMETRICAL SCHIFF-BASE COMPLEX ARISING FROM REARRANGEMENT OF THE FORMER [J].
GARCIADEIBE, A ;
BERMEJO, MR ;
SOUSA, A ;
MCAULIFFE, CA ;
MCGLYNN, P ;
NDIFON, PT ;
PRITCHARD, RG .
JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS, 1993, (10) :1605-1610