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Design, synthesis, and applications of chiral N-2-phenyl-2-propyl sulfinyl imines for group-assisted purification (GAP) asymmetric synthesis.

ABSTRACT: A new chiral (Rs)-2-phenyl-2-propyl sulfinamide has been designed and synthesized; its derived aldimines and ketimines have been applied for asymmetric addition reaction with allylmagnesium bromide. The reaction was conveniently performed at room temperature to give a series of homoallylic amines in high yields (up to quant) and diastereoselectivity (up to >99% de). The pure products were obtained by relying on group-assisted purification (GAP) chemistry to avoid traditional purification methods of column chromatography or recrystallization. The conversion of disulfide to (R(s))-thiosulfinate which contains a newly generated polar group was also confirmed to be of the GAP chemistry in which washing crude product can generate pure enantiomer. The absolute stereochemistry has been determined by X-ray analysis.

SUBMITTER: Pindi S

PROVIDER: S-EPMC3631466 | biostudies-other | 2013 Apr

REPOSITORIES: biostudies-other

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Design, synthesis, and applications of chiral N-2-phenyl-2-propyl sulfinyl imines for group-assisted purification (GAP) asymmetric synthesis.

Pindi Suresh S Wu Jianbin J Li Guigen G

The Journal of organic chemistry 20130326 8

A new chiral (Rs)-2-phenyl-2-propyl sulfinamide has been designed and synthesized; its derived aldimines and ketimines have been applied for asymmetric addition reaction with allylmagnesium bromide. The reaction was conveniently performed at room temperature to give a series of homoallylic amines in high yields (up to quant) and diastereoselectivity (up to >99% de). The pure products were obtained by relying on group-assisted purification (GAP) chemistry to avoid traditional purification methods ...[more]

PMID: 23496279

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