N,N-二甲基乙酰胺促进的羧酸肉桂酯的合成及其促进机理

在N,N-二甲基乙酰胺(DMAc)促进下,羧酸(1a～1v)依次与SOCl₂和肉桂醇反应合成了22个羧酸肉桂酯(2a～2v,其中2j, 2k, 2o, 2t和2v为新化合物),其结构经¹H NMR, ¹³C NMR, IR和MS(EI)表征。以巴豆酸肉桂酯(2i)的合成为例,研究了巴豆酸(1i)用量，肉桂醇用量，SOCl₂用量，DMAc用量对2i产率的影响和醇的加入方式对产物组成的影响。结果表明：在最优合成条件(1i 1.0 eq.,肉桂醇1.3 eq., SOCl₂ 1.3 eq., DMAc 2 mL, CH₂Cl₂ 6 mL,酰氯化后加入苄醇)下，2i产率82.2%。采用¹H NMR跟踪反应，确证了DMAc促进反应的机理。

N,N-Dimethylacetamide-promoted Synthesis of Cinnamyl Carboxylate and The Co-promoted Mechanism

Twenty two cinnamyl carboxylates(2a~2v, among them 2j, 2k, 2o, 2t and 2v were novel compounds) were synthesized by the N,N-dimethylacetamide( DMAc)-promoted reaction of carboxylic (1a~1v) with SOCl2 and cinnamyl alcohol, respectively. The structures were characterized by 1 H NMR, 13C NMR, IR and MS(EI). Effects of the dosage of crotonic acid(1i), cinnamic alcohol, SOCl2 and DMAc on yield of cinnamyl crotonate(2i) and the addition protocol of alcohol on products composition were investigated, using the synthsis of 2i as example. The results indicated that under the optimized reaction conditions(1i 1. 0 eq. , cinnamic alcohol 1. 3 eq. , SOCl21. 3 eq. , DMAc 2 mL, CH2Cl26 mL, adding benzyl alcohol after acylation), the yield of 2i was 82. 2%. The co-promoted mechanism of DMAc was confirmed by 1 H NMR tracing results.