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Enantioselective phase-transfer catalyzed alkylation of 1-methyl-7-methoxy-2-tetralone: an effective route to dezocine.

ABSTRACT: In order to prepare asymmetrically (R)-(+)-1-(5-bromopentyl)-1-methyl-7-methoxy-2-tetralone (3a), a key intermediate of dezocine, 17 cinchona alkaloid-derived catalysts were prepared and screened for the enantioselective alkylation of 1-methyl-7-methoxy-2-tetralone with 1,5-dibromopentane, and the best catalyst (C7) was identified. In addition, optimizations of the alkylation were carried out so that the process became practical and effective.

SUBMITTER: Li R

PROVIDER: S-EPMC6009193 | biostudies-other | 2018

REPOSITORIES: biostudies-other

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Enantioselective phase-transfer catalyzed alkylation of 1-methyl-7-methoxy-2-tetralone: an effective route to dezocine.

Li Ruipeng R Liu Zhenren Z Chen Liang L Pan Jing J Zhou Weicheng W

Beilstein journal of organic chemistry 20180611

In order to prepare asymmetrically (R)-(+)-1-(5-bromopentyl)-1-methyl-7-methoxy-2-tetralone (3a), a key intermediate of dezocine, 17 cinchona alkaloid-derived catalysts were prepared and screened for the enantioselective alkylation of 1-methyl-7-methoxy-2-tetralone with 1,5-dibromopentane, and the best catalyst (C7) was identified. In addition, optimizations of the alkylation were carried out so that the process became practical and effective. ...[more]

PMID: 29977405

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