One-pot synthesis of five-membered cyclic thioethers or ethers via intramolecular nitrile oxide-olefin cycloaddition (INOC) or intramolecular alkoxycarbonyl nitronate-olefin cycloaddition (IAOC) by the use of methyl chloroformate
作者:Ming-Chung Yan、Jing-Yuan Liu、Wen-Wei Lin、Kuo-Hsi Kao、Ju-Tsung Liu、Jeong-Jiunn Jang、Ching-Fa Yao
DOI:10.1016/s0040-4020(99)00741-3
日期:1999.10
with allyl alcohol and base, can be converted into methoxycarbonyl nitronates 22 by treating the solution with methyl chloroformate and calytic amount of 4-dimethylaminopyridine (DMAP) in the presence of different amounts of triethylamine. Intermediates 22 can either undergo intramolecular alkoxycarbonyl nitronate-olefin cycloaddition (IAOC) to generate highly stereoselective product trans-14 or undergo
β-硝基苯乙烯的反应1与烯丙基硫醇2在三乙胺存在下产生的不饱和硝基硫化物3,然后将溶液用氯甲酸甲酯(MCF)处理并回流以获得[3.3.0]双环产品反式- 6和顺式-一锅6个。的口粮反式- 6:顺式- 6是从1.1:1至1.8:1和地层的机构6,提出了通过腈氧化物的形成进行5经受分子内氧化腈烯烃环加成(INOC)。亚硝酸盐16,从制备1用烯丙醇和碱,可被转化为甲氧基羰基nitronates 22通过用氯甲酸甲酯和不同量的三乙胺的存在下4-二甲基氨基吡啶(DMAP)的calytic量的溶液。中间体22可以经历分子内烷氧基羰基氮酸盐烯烃环加成(IAOC),以生成高立体选择性产物反式- 14或经历INOC,得到反式- 14个及顺式- 14。此改进方法的应用可合成不同的杂环产物10、26和报告了27。