757954-58-8Relevant academic research and scientific papers
Probing the importance of the hemilabile site of bis(phosphine) monoxide ligands in the copper-catalyzed addition of diethylzinc to N-phosphinoylimines: Discovery of new effective chiral ligands
Bonnaventure, Isabelle,Charette, Andre B.
, p. 6330 - 6340 (2008/12/22)
(Chemical Equation Presented) The hemilabile ligand Me-DuPHOS(O) 2 has proven to be a successful ligand for the copper-catalyzed addition of diethylzinc to N-phosphinoylimines. The corresponding α-chiral amines were obtained in high yields (80-98%) and enantiomeric ratios (19.0:1 to 99.0:1 er). Furthermore, this Cu?2 catalytic system has been shown to be effective in the addition of diethylzinc to nitroalkenes and in the reduction of β,β-disubstituted vinyl phenyl sulfones. This paper describes a general structure/selectivity study in which the three ligand subunits (chiral phospholane-linker-labile coordinating group (Z)) are systematically modified and tested in the copper-catalyzed addition of diethylzinc to the N-phosphinoylimine 1 derived from benzaldehyde. This study led to the discovery of a new class of effective chiral ligands that combine a chiral phospholane unit and an achiral phosphine oxide.
Preparation of P-chirogenic phospholanes and their use in asymmetric synthesis
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Page/Page column 13, (2010/02/14)
Materials and methods for preparing P-chirogenic monophospholanes and bisphospholanes are disclosed. The methods employ stereoselective cyclization to generate the phospholane rings followed by pyramidal inversion to access a variety of P-chirogenic phosp
Stereoselective cyclization and pyramidal inversion strategies for P-chirogenic phospholane synthesis
Hoge, Garrett
, p. 9920 - 9921 (2007/10/03)
Preparation of P-chirogenic mono- and bisphospholanes is reported. The demonstrated method employs a stereoselective cyclization of cyclic sulfates with primary phosphines in the presence of base to generate "cis" or "cis/cis" P-chirogenic phospholanes followed by heat-induced pyramidal inversion to provide "trans" or "trans/trans" P-chirogenic phospholanes. A rhodium complex of one "trans/trans" phospholane is applied to the highly enantioselective asymmetric hydrogenation of a substrate precursor to the pharmaceutical candidate pregabalin. Copyright
