952679-06-0Relevant academic research and scientific papers
Preparation of chiral phosphinoferrocene carboxamide ligands and their application to palladium-catalyzed asymmetric allylic alkylation
Lamac, Martin,Tauchman, Jiri,Cisarova, Ivana,Stepnicka, Petr
, p. 5042 - 5049 (2008/10/09)
A series of phosphinoferrocene carboxamides bearing achiral (benzyl) and chiral [(R)- and (S)-1phenylethyl] substituents at the amide nitrogen have been prepared from 1′-(diphenylphosphino)ferrocenecarboxylic (Hdpf) and (S p)-2-(diphenylphosphino)ferrocenecarboxylic ((Sp)-1) acids and tested as ligands for enantioselective allylic alkylation of 1,3-diphenylallyl acetate with dimethyl malonate. At room temperature, the alkylation reactions proceeded with complete conversions and ee's up to 90%, the most efficient being the planar-only chiral ligand (Sp)-2- (diphenylphosphino)-l-(N-benzylcarbamoyl)ferrocene ((Sp)-2). The crystal structures of (Sp)-2 and the cationic (η3- allyl)palladium(II) complex [Pd(η3-1,3-Ph2C 3H3){(Sp)-2-K2O,.P}]ClO4 ((Sp)-8) have been determined by single-crystal X-ray diffraction and solution NMR data were obtained to provide an insight into the mechanism of chiral discrimination.
