Addition of dimethyl phosphite to imines bearing the L-methionine moiety and its surprisingly poor chiral assistance
作者:Jarosław Lewkowski、Rafał Karpowicz
DOI:10.1002/hc.21029
日期:——
The preparation of methyl 2-[(dimethoxyphosphoryl)-methyl]-amino}-4-methyl- sulfanylbutyrates (3a–e) by the addition of dimethylphosphite to 2-(methylidenamino)-4-methylsulfanylbutyric acid methyl esters (2a–e) is described. The nearly nonexisting diastereoselectivity, which was observed in all cases, is unexpected and astonishing in light of the fact that some other amino acid esters, e.g., leucine