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Aldol Reactions of Axially Chiral 5-Methyl-2-(o-aryl)imino-3-(o-aryl)-thiazolidine-4-ones.

ABSTRACT: Axially chiral 5-methyl-2-(o-aryl)imino-3-(o-aryl)-thiazolidine-4-ones have been subjected to aldol reactions with benzaldehyde to produce secondary carbinols which have been found to be separable by HPLC on a chiral stationary phase. Based on the reaction done on a single enantiomer resolved via a chromatographic separation from a racemic mixture of 5-methyl-2-(?-naphthyl)imino-3-(?-naphthyl)-thiazolidine-4-one by HPLC on a chiral stationary phase, the aldol reaction was shown to proceed via an enolate intermediate. The axially chiral enolate of the thiazolidine-4-one was found to shield one face of the heterocyclic ring rendering face selectivity with respect to the enolate. The selectivities observed at C-5 of the ring varied from none to 11.5:1 depending on the size of the ortho substituent. Although the aldol reaction proceeded with a lack of face selectivity with respect to benzaldehyde, recrystallization returned highly diastereomerically enriched products.

SUBMITTER: Erol Gunal S

PROVIDER: S-EPMC6274475 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature

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Aldol Reactions of Axially Chiral 5-Methyl-2-(o-aryl)imino-3-(o-aryl)-thiazolidine-4-ones.

Erol Gunal Sule S Dogan Ilknur I

Molecules (Basel, Switzerland) 20160618 6

Axially chiral 5-methyl-2-(o-aryl)imino-3-(o-aryl)-thiazolidine-4-ones have been subjected to aldol reactions with benzaldehyde to produce secondary carbinols which have been found to be separable by HPLC on a chiral stationary phase. Based on the reaction done on a single enantiomer resolved via a chromatographic separation from a racemic mixture of 5-methyl-2-(α-naphthyl)imino-3-(α-naphthyl)-thiazolidine-4-one by HPLC on a chiral stationary phase, the aldol reaction was shown to proceed via an ...[more]

PMID: 27322237

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