Highly Enantioselective Aryl Transfer to Aldehydes: A Remarkable Effect of Sulfur Substitution in Amino Thioacetate Ligands
摘要:
Chiral amino thioacetate ligands were prepared from the corresponding amino alcohols and used as catalysts for enantioselective aryl transfer reaction. The amino thioacetates were remarkably superior to the corresponding amino alcohols, Low catalyst loadings of only 1-2.5 mol % were sufficient to achieve excellent enantioselectivity as well as high conversion in short reaction time. The results reveal that the thioacetoxy moiety of the amino thioacetates has a surprisingly beneficial effect in enhancing the asymmetric induction.
Enantioselective addition of diethylzinc to α-branched aldehydes
作者:Jahyo Kang、Jun Won Lee、Joo In Kim
DOI:10.1039/c39940002009
日期:——
Reaction of diethylzinc with α-branched aldehydes in the presence of a catalytic amount of (1R,2S)-(â)-1-phenyl-2-piperidinopropane-1-thiol 1 provided the corresponding secondary alcohols in almost 100% enantiomeric excess.
Highly Enantioselective Aryl Transfer to Aldehydes: A Remarkable Effect of Sulfur Substitution in Amino Thioacetate Ligands
作者:Myung-Jong Jin、Shaheen M. Sarkar、Dong-Hwan Lee、Huili Qiu
DOI:10.1021/ol8001249
日期:2008.3.1
Chiral amino thioacetate ligands were prepared from the corresponding amino alcohols and used as catalysts for enantioselective aryl transfer reaction. The amino thioacetates were remarkably superior to the corresponding amino alcohols, Low catalyst loadings of only 1-2.5 mol % were sufficient to achieve excellent enantioselectivity as well as high conversion in short reaction time. The results reveal that the thioacetoxy moiety of the amino thioacetates has a surprisingly beneficial effect in enhancing the asymmetric induction.