invertive B-alkyl Suzuki-Miyaura coupling has been achieved. The coupling of enantioenriched α-(acylamino)benzylboronic esters with aryl bromides and chlorides took place efficiently in toluene at 80 °C in the presence of Pd(dba)(2) (5 mol %), XPhos (10 mol %), K(2)CO(3) (3 equiv), and H(2)O (2 equiv). The reaction proceeded with inversion of configuration to give diarylmethanamine derivatives in high
Bis-Sulfamyl Imines: Potent Substrates for Asymmetric Additions of Arylboroxines under Rhodium Catalysis
作者:Rosemary Crampton、Simon Woodward、Martin Fox
DOI:10.1002/adsc.201000838
日期:2011.4.18
Bis‐sulfamyl imines are shown to be potentially ideal substrates for rhodium‐catalysed asymmetricadditions of arylboron nucleophiles as they show: (i) near perfect enantioselectivities (11 examples, 98–99+% ee), (ii) good to excellent diastereoselectivities (10–32:1 rac:meso), and (iii) high functional group tolerance in removal of the low molecular weight protecting group via mild heating in aqueous
Homogeneous asymmetric hydrogenation of unprotected benzophenone N-H imines 1a-r using 1r-benzyl-N-methyl-MonoPhos as a catalyst provides chiral amines 2a-r in 80-96% yield with enantioselectivities up to 98% ee (18 examples) for ortho-substituted substrates.