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Asymmetric synthesis of ?-amino-1,3-dithianes via chiral N-phosphonyl imine-based Umpolung reaction without using chromatography and recrystallization.

ABSTRACT: A series of ?-amino-1,3-dithianes have been synthesized via the asymmetric Umpolung reaction of 2-lithio-1,3-dithianes with chiral N-phosphonyl imines in good chemical yields (up to 82%) and good to excellent diastereoselectivities (>99:1). The manner by which chiral N-phosphonyl imines are slowly added into the solution of 2-lithio-1,3-dithiane was found to be crucial for achieving excellent diastereoselectivity. The current synthesis was proven to follow the GAP chemistry (group-assistant-purification chemistry) process, which avoids traditional purification techniques of chromatography or recrystallization, i.e., the pure chiral ?-amino-1,3-dithianes attached with the chiral N-phosphonyl group were readily obtained by washing the solid crude products with hexane or a mixture of hexane-ethyl acetate.

SUBMITTER: Kattamuri PV

PROVIDER: S-EPMC3074014 | biostudies-literature | 2011 Apr

REPOSITORIES: biostudies-literature

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Asymmetric synthesis of α-amino-1,3-dithianes via chiral N-phosphonyl imine-based Umpolung reaction without using chromatography and recrystallization.

Kattamuri Padmanabha V PV Ai Teng T Pindi Suresh S Sun Yinwei Y Gu Peng P Shi Min M Li Guigen G

The Journal of organic chemistry 20110315 8

A series of α-amino-1,3-dithianes have been synthesized via the asymmetric Umpolung reaction of 2-lithio-1,3-dithianes with chiral N-phosphonyl imines in good chemical yields (up to 82%) and good to excellent diastereoselectivities (>99:1). The manner by which chiral N-phosphonyl imines are slowly added into the solution of 2-lithio-1,3-dithiane was found to be crucial for achieving excellent diastereoselectivity. The current synthesis was proven to follow the GAP chemistry (group-assistant-puri ...[more]

PMID: 21405041

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