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Ca(OH)2-Catalyzed Condensation of Aldehydes with Methyl ketones in Dilute Aqueous Ethanol: A Comprehensive Access to ?,?-Unsaturated Ketones.

ABSTRACT: Cheap, abundant but seldom-employed Ca(OH)2 was found to be an excellent low-loading (5-10?mol%) catalyst for Claisen-Schmidt condensation of aldehydes with methyl ketones under mild conditions. It was interesting that dilute aqueous ethanol (20?v/v%) was unexpectedly discovered to be the optimal solvent. The reaction was scalable at least to 100?mmol and calcium could be precipitated by CO2 and removed by filtration. Evaporation of solvent directly afforded the product in the excellent 96% yield with high purity, as confirmed by its (1)H NMR spectrum.

SUBMITTER: Yu L

PROVIDER: S-EPMC4957220 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature

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Ca(OH)2-Catalyzed Condensation of Aldehydes with Methyl ketones in Dilute Aqueous Ethanol: A Comprehensive Access to α,β-Unsaturated Ketones.

Yu Lei L Han Mengting M Luan Jie J Xu Lin L Ding Yuanhua Y Xu Qing Q

Scientific reports 20160722

Cheap, abundant but seldom-employed Ca(OH)2 was found to be an excellent low-loading (5-10 mol%) catalyst for Claisen-Schmidt condensation of aldehydes with methyl ketones under mild conditions. It was interesting that dilute aqueous ethanol (20 v/v%) was unexpectedly discovered to be the optimal solvent. The reaction was scalable at least to 100 mmol and calcium could be precipitated by CO2 and removed by filtration. Evaporation of solvent directly afforded the product in the excellent 96% yiel ...[more]

PMID: 27443482

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