Stereoselective addition reactions of chiral N-benzylidene-p-toluenesulfinamides. Asymmetric syntheses of .beta.- and .gamma.-amino acids
摘要:
Chiral N-benzylidene-p-toluenesulfinamides 2 were prepared by the reaction of benzonitrile with alkyllithium in ether followed by (-)-l-menthyl (S)-p-tolylsulfinate. Treatment of 2 with allylmagnesium bromide in ether at 0-degrees-C gave the adducts (R)-7 with excellent stereoselectivity. Pure chiral sulfinamides 7 were converted into chiral beta- and gamma-amino acids in four and five steps, respectively.
Stereoselective addition reactions of chiral N-benzylidene-p-toluenesulfinamides. Asymmetric syntheses of .beta.- and .gamma.-amino acids
摘要:
Chiral N-benzylidene-p-toluenesulfinamides 2 were prepared by the reaction of benzonitrile with alkyllithium in ether followed by (-)-l-menthyl (S)-p-tolylsulfinate. Treatment of 2 with allylmagnesium bromide in ether at 0-degrees-C gave the adducts (R)-7 with excellent stereoselectivity. Pure chiral sulfinamides 7 were converted into chiral beta- and gamma-amino acids in four and five steps, respectively.
Copper-catalyzed asymmetric allylation of chiral N-tert-butanesulfinyl imines: dual stereocontrol with nearly perfect diastereoselectivity
作者:Yi-Shuang Zhao、Qiang Liu、Ping Tian、Jing-Chao Tao、Guo-Qiang Lin
DOI:10.1039/c5ob00322a
日期:——
Copper-catalyzed asymmetric allylation of chiral N-tert-butanesulfinyl imines has been described. Dual stereocontrol, through the combination of a chiral auxiliary and a chiral copper complex, has played an important role in achieving the nearly perfect diastereoselectivities (all dr > 99 : 1), especially for ketimine substrates.