Phosphinoyl ketimines

Addition to C=N bond. Strecker-type synthesis, the addition of MesSiCN to imines, on extending to AT-phosphinoyl ketimines is enantioselective in the presence of 86, and the optimal conditions involve the addition of 10 mol% of MCPBA. ... 

A highly enantioselective Meerwein-Schmidt-Ponndorf-Verley (MSPV) reduction of N-phosphinoyl ketimines by (BINOL)Al(iii)/2-propanol has been reported. High yields and enantiomeric excesses were observed for a wide range of structurally diverse ketimines. A [2.0.4] bicyclic chelation model was proposed to account for the... 

A -Phosphinoyl and A -thiophosphinoyl ketimines, Ph-C(Me)=N-P(=X)Ph2 (X = O and S), have been hydrophosphonylated in high yield and ee using a copper(I) catalyst liganded with a chiral diphosphino ethane. In the case of the sulfur substrates, facile differentiated removal of the t/imphosphinoyl group affords a-amino phosphonic acid derivatives, Ph- C(Me)(NH2)-P(=0)(0Et)2, that is, phosphonic acid analogues of enantio-enriched a,a-disubstituted a-amino acids. The reaction also accommodates alkyl, cycloalkyl and alkenyl substituents in place of the phenyl. 

Scheme 30.15 Strecker reaction of phosphinoyl ketimines by an in situ prepared catalyst.

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