One-pot synthesis of cyclic aldol tetramer and ?, β-unsaturated aldol from linear aldehydes using quaternary ammonium combined with sodium hydroxide as catalysts  

作　　者：许海峰 钟宏 王帅 李方旭 

机构地区：[1]School of Chemistry and Chemical Engineering, Central South University [2]Key Laboratory of Resources Chemistry of Nonferrous Metals of Ministry of Education (Central South University)

出　　处：《Journal of Central South University》2015年第6期2081-2087,共7页中南大学学报（英文版）

基　　金：Project(2013AA064102)supported by the National High-Tech Research Program of China;Project(11JJ6014)supported by the Hunan Provincial Natural Science Foundation of China

摘　　要：One-pot synthesis of cyclic aldol tetramer and α, β-unsaturated aldol from C3-C8 linear aldehydes using phase-transfer catalyst（PTC）, quaternary ammonium, combined with sodium hydroxide as catalysts was investigated. Butanal was subjected for detail investigations to study the effect of parameters. It was found that the selectivity of cyclic aldol tetramer depends greatly on the operating conditions of the reaction, especially the PTC/butanal molar ratio. The average selectivity of 2-hydroxy-6-propyl-l, 3, 5-triethyl-3-cyclohexene-1-carboxaldehyde（HPTECHCA） was 54.41% using tetrabutylammonium chloride combined with 14%（mass fraction） Na OH as catalysts at 60 ℃for 2 h with a PTC-to-butanal molar ratio of 0.09：1. Pentanal was more likely to generate cyclic aldol tetramer compared with other aldehydes under the optimum experimental conditions. Recovery of the PTC through water washing followed by adding enough sodium hydroxide from the washings was also demonstrated.One-pot synthesis of cyclic aldol tetramer and α, β-unsaturated aldol from C3-C8 linear aldehydes using phase-transfer catalyst(PTC), quaternary ammonium, combined with sodium hydroxide as catalysts was investigated. Butanal was subjected for detail investigations to study the effect of parameters. It was found that the selectivity of cyclic aldol tetramer depends greatly on the operating conditions of the reaction, especially the PTC/butanal molar ratio. The average selectivity of 2-hydroxy-6-propyl-l, 3, 5-triethyl-3-cyclohexene-1-carboxaldehyde(HPTECHCA) was 54.41% using tetrabutylammonium chloride combined with 14%(mass fraction) Na OH as catalysts at 60 °C for 2 h with a PTC-to-butanal molar ratio of 0.09:1. Pentanal was more likely to generate cyclic aldol tetramer compared with other aldehydes under the optimum experimental conditions. Recovery of the PTC through water washing followed by adding enough sodium hydroxide from the washings was also demonstrated.

关 键 词：aldol condensation one-pot synthesis phase-transfer catalyst ALDEHYDE 

分 类 号：TQ317[化学工程—高聚物工业] O643.36[理学—物理化学]