Bisphosphine oxides formed highlyactiveasymmetric Heck catalysts, which were applied in asymmetricsynthesis of pharmacologically active azacycles. Olefin insertion proceeded via cis pathways, different from P,N-ligands.
Selective mono reduction of bis-phosphine oxides under mild conditions
作者:Maria J. Petersson、Wendy A. Loughlin、Ian D. Jenkins
DOI:10.1039/b807695b
日期:——
Bis-phosphine oxides can be selectively reduced to bis-phosphine monoxides under exceptionally mild conditions using triflic anhydride and a thiol.
在非常温和的条件下,使用三氟磺酸酐和硫醇,可以将双膦氧化物选择性地还原为双膦单氧化物。
SPIRO-1,1'-BINDANE-7,7-BISPHOSPHINE OXIDES AS HIGHLY ACTIVE SUPPORTING LIGANDS FOR PALADIUM-CATALYZED ASYMMETRIC HECK REACTION
申请人:NANYANG TECHNOLOGICAL UNIVERSITY
公开号:US20160136629A1
公开(公告)日:2016-05-19
The present invention relates to catalyst complexes comprising palladium (Pd) and at least one spiro-1,1′-biindane-7,7′-bisphosphine oxide ligand as disclosed herein, and their use. The present invention is further directed to the asymmetric catalyzed covalent carbon-carbon single bond formation from aryl, heteroaryl and alkenyl triflates and halides and olefins utilising the said catalyst complexes.
An Application of Electronic Asymmetry to Highly Enantioselective Catalytic Diels−Alder Reactions
作者:J. W. Faller、Brian J. Grimmond、Darlene G. D'Alliessi
DOI:10.1021/ja003528c
日期:2001.3.1
The compounds (R-Ru)-[CyRuCl(S)-BINPO]SbF6 and [CyRuCl(S)-TolBINPO]SbF6 (Cy = eta (6)-cymene), were synthesized from (CyRuCl2)(2) and the appropriate non-C-2-symmetric bisphosphine monoxide ligands (S)-BINPO and (S)-TolBINPO (BINPO = 2,2 ' -bis(dipbenylphosphino)-1,1 ' -binaphthyl) in the presence of NaSbF6. When these complexes were mixed with AgSbF6 the resulting Lewis acids catalyzed the Diels-Alder cycloaddition of cyclopentadiene and methacrolein. The product, (2S)-methylbicyclo[2.2.1]hept-5-ene-2-carboxaldehyde was obtained with excellent diastereoselectivity (up to 99%) and enantioselectivity (up to 99%) in several cases. When the complexes containing the analogous C-2-symmetric bisphosphine;ligands (S)-BINAP and (S)-TolBINAP were employed as catalysts, the Diels-Alder cycloadducts were obtained with much lower enantioselectivity (19 to 50%) for the opposite antipode. Although some of the effect may arise from chelate ring size change, much of the enhanced stereoselectivity of (R-Ru)-[CyRuCl(S)-BINPO] SbF6 and [CyRuCl(S)-TolBINPO]SbF6 can be attributed to the electronic asymmetry at the stereogenic Ru center.