Catalytic Enantioselective Synthesis of Chiral Isatin Derivatives by an Aldol Approach
作者:Akira Yanagisawa、Naoyuki Kushihara、Takuya Sugita、Kazuhiro Yoshida
DOI:10.1055/s-0032-1316551
日期:2012.7
A catalytic enantioselective aldol reaction of alkenyl esters with isatins was achieved using an (S)-BINOL-derived chiraltin dibromide possessing a 4-tert-butylphenyl group at 3- and 3′-positions as the chiral pre-catalyst in the presence of sodium methoxide and methanol. Optically active 3-alkylated 3-hydroxy-2-oxindoles having up to 98% ee were diastereoselectively obtained in high yields not only
Enantioselective Nitroso Aldol Reaction Catalyzed by QuinoxP*·Silver(I) Complex and Tin Methoxide
作者:Akira Yanagisawa、Satoshi Takeshita、Youhei Izumi、Kazuhiro Yoshida
DOI:10.1021/ja910588w
日期:2010.4.21
A catalytic enantioselective O-nitroso aldol reaction of alkenyl trichloroacetates with nitrosoarenes was achieved using the (R,R)-t-Bu-QuinoxP*.AgOAc complex as the chiral catalyst and Bu(2)Sn(OMe)(2) as the achiral cocatalyst in the presence of methanol. Optically active alpha-aminooxy ketones with up to 99% ee were regioselectively obtained in high yields from various alkenyl trichloroacetates of
使用 (R,R)-t-Bu-QuinoxP*.AgOAc 配合物作为手性催化剂和 Bu(2)Sn(OMe)(2) 作为手性催化剂,实现了烯基三氯乙酸酯与亚硝基芳烃的催化对映选择性 O-亚硝基羟醛反应在甲醇存在下的非手性助催化剂。具有高达 99% ee 的光学活性 α-氨基氧基酮以高产率从环酮的各种烯基三氯乙酸酯中获得。