Article

Enantioselective synthesis of (R)- and (S)-alpha-alkylcysteines via phase-transfer catalytic alkylation.

Research Institute of Pharmaceutical Science and College of Pharmacy, Seoul National University, Seoul 151-742, Korea.
The Journal of Organic Chemistry (Impact Factor: 4.56). 10/2006; 71(21):8276-8. DOI: 10.1021/jo061107t
Source: PubMed

ABSTRACT We reported efficient enantioselective synthetic methodologies for (R)-alpha-alkylcysteines and (S)-alpha-alkylcysteines. The phase-transfer catalytic alkylation of 2-phenyl-2-thiazoline-4-carboxylic acid tert-butyl ester and 2-o-biphenyl-2-thiazoline-4-carboxylic acid tert-butyl ester, in the presence of chiral catalysts (1 or 2), gave the corresponding alkylated products, which could be hydrolyzed to provide (R)-alpha-alkylcysteines (67->99% ee) and (S)-alpha-alkylcysteines (66-88% ee), respectively.

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