Synthesis of Novel Bidentate P-Chiral Diaminophosphine Oxide Preligands: Application to Pd-Catalyzed Asymmetric Allylic Substitution Reactions
作者:Teisuke Harada、Tetsuhiro Nemoto、Long Jin、Yasumasa Hamada
DOI:10.1248/cpb.59.412
日期:——
We developed a novel (S)-L-phenylalanine derived-bidentate chiral diaminophosphine oxide (DIAPHOX) preligand (S,SP)-9b, which was successfully applied to Pd-catalyzed asymmetric allylic alkylation and amination. Using the Pd-(S,SP)-9b catalyst system, asymmetric allylic alkylation and amination proceeded very smoothly, affording the corresponding products in excellent yield with high enantiomeric excess. It is noteworthy that both enantiomers were accessible with high enantiomeric purity using the structurally related DIAPHOX preligands (S,SP)-9b and a monodentate chiral diaminophosphine oxide preligand (S,RP)-10a, both of which can be prepared from a single chiral source, (S)-L-phenylalanine.
我们开发了一种新型的(S)-L-苯丙氨酸衍生的双齿手性二氨基磷氧化物(DIAPHOX)预配体(S,SP)-9b,并成功应用于钯催化的不对称烯丙基烷基化和胺化反应。使用钯-(S,SP)-9b催化体系,不对称烯丙基烷基化和胺化反应顺利进行,产率极高,对映体过量值也很高。值得注意的是,使用结构相关的DIAPHOX预配体(S,SP)-9b和单齿手性二氨基磷氧化物预配体(S,RP)-10a,均可以从单一的手性源(S)-L-苯丙氨酸制备,两种配体都能获得高对映体纯度的两种对映异构体。