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Asymmetric Michael addition reactions catalyzed by calix[4]thiourea cyclohexanediamine derivatives.

ABSTRACT: A number of upper rim-functionalized calix[4]thiourea cyclohexanediamine derivatives have been designed, synthesized and used as catalysts for enantioselective Michael addition reactions between nitroolefins and acetylacetone. The optimal catalyst 2 with a mono-thiourea group exhibited good performance in the presence of water/toluene (v/v = 1:2). Under the optimal reaction conditions, high yields of up to 99% and moderate to good enantioselectivities up to 94% ee were achieved. Detailed experiments clearly showed that the upper rim-functionalized hydrophobic calixarene scaffold played an important role in cooperation with the catalytic center to the good reactivities and enantioselectivities.

SUBMITTER: Li ZY

PROVIDER: S-EPMC6071695 | biostudies-literature | 2018

REPOSITORIES: biostudies-literature

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Asymmetric Michael addition reactions catalyzed by calix[4]thiourea cyclohexanediamine derivatives.

Li Zheng-Yi ZY Tong Hong-Xiao HX Chen Yuan Y Su Hong-Kui HK Xiao Tangxin T Sun Xiao-Qiang XQ Wang Leyong L

Beilstein journal of organic chemistry 20180725

A number of upper rim-functionalized calix[4]thiourea cyclohexanediamine derivatives have been designed, synthesized and used as catalysts for enantioselective Michael addition reactions between nitroolefins and acetylacetone. The optimal catalyst <b>2</b> with a mono-thiourea group exhibited good performance in the presence of water/toluene (v/v = 1:2). Under the optimal reaction conditions, high yields of up to 99% and moderate to good enantioselectivities up to 94% ee were achieved. Detailed ...[more]

PMID: 30112095

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