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Synthesis of chiral N-phosphinyl ?-imino esters and their application in asymmetric synthesis of ?-amino esters by reduction.

ABSTRACT: A variety of chiral N-phosphinyl ?-imino esters have been synthesized for the first time from ketoesters and phosphinylamide, which were then reduced by L-selectride to give the corresponding N-phosphinyl-protected ?-amino esters. The reduction proceeded very well with excellent chemical yields (88-98%) as well as high diastereoselectivities (96:4 to 99:1). Some of these products could be obtained without column chromatography and recrystallization. The chiral phosphinyl auxiliary could be easily cleaved under acidic conditions.

SUBMITTER: Xiong Y

PROVIDER: S-EPMC3999852 | biostudies-other | 2014

REPOSITORIES: biostudies-other

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Synthesis of chiral N-phosphinyl α-imino esters and their application in asymmetric synthesis of α-amino esters by reduction.

Xiong Yiwen Y Mei Haibo H Wu Lingmin L Han Jianlin J Pan Yi Y Li Guigen G

Beilstein journal of organic chemistry 20140313

A variety of chiral N-phosphinyl α-imino esters have been synthesized for the first time from ketoesters and phosphinylamide, which were then reduced by L-selectride to give the corresponding N-phosphinyl-protected α-amino esters. The reduction proceeded very well with excellent chemical yields (88-98%) as well as high diastereoselectivities (96:4 to 99:1). Some of these products could be obtained without column chromatography and recrystallization. The chiral phosphinyl auxiliary could be easil ...[more]

PMID: 24778716

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