178626-86-3Relevant articles and documents
Synthesis of water soluble fe and ru complexes novel thioether thiolate carboxylate substituents
Scllmann, Dieter,Backer, Thomas,Enoch, Falk
, p. 509 - 519 (2007/10/03)
In search of water soluble transition metal complexes with sulfur dominated coordination spheres that model key reactions of nitrogenases, the benzenedithiol derivatives 'CO2HS2'-H2 (I) and 'CO2Me-S2'-H2 (2) were synthesized as precursors for multidentate sulfur ligands. The template alkylation of 2 by C2H4Br2 at [Fe(CO)2] fragments yielded a mixture of two diastereomeric C2 symmetrical [Fe(CO)2('CO2Me-S4'}] complexes (4a and 4b), which were separated by crystallization. The hydrolysis of the mixture of the diastereomers 4a and 4b led to the isomerically pure tetradentate thioether thiol ligand 'CO2Me-S4'-H2 (5) proving the regioselectivity of the template alkylation ol the asymmetrical dithiol 2. The Q symmetrical [Fe{'CO2Me-S2')2]2~ anion is an intermediate of the template alkylation and was isolated as (AsPh4)2[Fe('CO2Me-S2'}2] (11). 4a, 5 and 11 were characterized by Xray structural analysis. Saponification of the methyl ester groups of 5 yielded 'CO2H-S4'-H2 (7). Treatment of 7 with FeCl2 · 4 H2O in the presence of CO and LiOMe gave a mixture of two C2 symmetrical and water soluble diastereomers of Li2SFe(CO)2('CO2-S4')] (8). Upon treatment with [RuCl2(PPh3)3], 7 yielded isomerically pure [Ru(PPh3)2-('CO2H-S4')] (9). 9 also exhibits C2 symmetry and could be reversibly deprotonated to form the water soluble complex K2[Ru(PPh3)2('CO2-S4')] (10). Treatment of (NBu4)2(CO2MeS2') with "Ru(NO)Cl3" led to isomerically pure (NBu4)[Ru(NO)('CO2Me-S2')2] (12). VCH Verlagsgesellschaft mbH, , 1996.