2-己基-4-乙酰氧基四氢噻吩顺反立体异构体制备及香气特性-《中国调味品》

文章信息/Info

Title:: Preparation and sensory properties of cis- and trans-isomers of 2-hexyl-4-acetoxytetrahydrofuran

摘要:: 本文以烯丙基氯和正庚醛为原料，首先将烯丙基氯制成烯丙基氯化镁，与正庚醛经格氏反应得到1-癸烯-4-醇，产率为87%；1-癸烯-4-醇用间氯过氧苯甲酸氧化，转变为1,2-环氧-4-癸醇，产率为93%；环氧醇在三乙胺的作用下与甲磺酰氯反应，得到1,2-环氧-4-癸基甲磺酸酯，产率为78%；1,2-环氧-4-庚基甲磺酸酯在碳酸钾存在下与硫代醋酸反应，得到2-己基-4-乙酰氧基四氢噻吩的两个顺反立体异构体，产率分别为39%和43%。产物的顺反相对构型经过NOE谱图进行了确认。两个顺反立体异构体的香气特征和香气阈值通过GC/O进行了评价和测定，两个异构体表现出明显不同的香气特性。

Abstract:: 2-Hexyl-4-acetoxytetrahydrothiophene was prepared, which started from allyl magnesium chloride and n-heptanal through the Grignard reaction to give 1-decen-4-ol in 87% yield, then the obtained 1-decen-4-ol was epoxidized with MCPBA to produce 1,2-epoxy-4-decanol in 93% yield, mesylation produced 1,2-epoxy-4-heptyl mesylate in 78% yield, treatment with thioacetic acid in the presence of potassium carbonate to afford cis- and trans- 2-hexyl-4-acetoxytetrahydrothiophene in 39% and 43% yields respectively. The relative configuration of two stereoisomers was identified by NOE spectra. The odor feature and thresholds were evaluated and determined by GC/O, which were very different for the two stereoisomers.