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Asymmetric synthesis of quaternary aryl amino acid derivatives via a three-component aryne coupling reaction.

ABSTRACT: A method was developed for the synthesis of ?-alkyl, ?-aryl-bislactim ethers in good to excellent yields and high diastereoselectivities, consisting of a facile one-pot procedure in which the aryl group is introduced by means of a nucleophilic addition to benzyne and the alkyl group by alkylation of a resultant benzylic anion. Hydrolysis of the sterically less hindered adducts gave the corresponding quaternary amino acids with no racemization, whereas hydrolytic ring opening gave the corresponding valine dipeptides from bulkier bislactims.

SUBMITTER: Jones EP

PROVIDER: S-EPMC3252860 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature

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Asymmetric synthesis of quaternary aryl amino acid derivatives via a three-component aryne coupling reaction.

Jones Elizabeth P EP Jones Peter P White Andrew J P AJ Barrett Anthony G M AG

Beilstein journal of organic chemistry 20111125

A method was developed for the synthesis of α-alkyl, α-aryl-bislactim ethers in good to excellent yields and high diastereoselectivities, consisting of a facile one-pot procedure in which the aryl group is introduced by means of a nucleophilic addition to benzyne and the alkyl group by alkylation of a resultant benzylic anion. Hydrolysis of the sterically less hindered adducts gave the corresponding quaternary amino acids with no racemization, whereas hydrolytic ring opening gave the correspondi ...[more]

PMID: 22238534

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