Palladium A-frame complexes containing carboxylato ligands. Synthesis of [Pd 2(O 2CR) 2{μ-C 2(CO 2Me) 2}(μ-Ph 2PCH 2SCH 2Ph) 2] and NMR evidence of the enantiotopic face in the side-by-side complex [Pd 2Cl 12(μ-Ph 2PCH 2SCH 2Ph) 2

Abstract

The A-frame complex [Pd 2Cl 2{μ;-C 2(CO 2Me) 2}(μ-Ph 2PCH 2SCH 2Ph) 2], obtained by the reaction between the side-by-side complex [Pd 2Cl 2(μ-Ph 2PCH 2SCH 2Ph) 2] ( 1) and dimethyl acetylenedicarboxylate, reacts with silver acetate and silver benzoate to give [Pd 2(O 2CR) 2{μ-C 2(CO 2Me) 2}(μ-Ph 2PCH 2SCH 2Ph) 2]·3H 2O [R = Me ( 3), Ph ( 4)]. Similar reactions with silver salts of ( S)- and racemic-2-phenylpropionic acid afford [Pd 2(O 2 CHMePh) 2{μ-C 2(CO 2Me) 2}(μ-Ph 2PCH 2SCH 2Ph) 2] [( S)- ( 5), racemic- ( 6)]. The NMR spectra of 5 and 6 show diastereoisomeric signal splitting, elucidating the presence of the enantiotopic face in 1.