1,3-dipolar cycloadditions of trimethylsilyldiazomethane revisited: steric demand of the dipolarophile and the influence on product distribution.
1,3-dipolar cycloadditions of trimethylsilyldiazomethane revisited: steric demand of the dipolarophile and the influence on product distribution.
复制标题
DOI：
10.1021/jo061838t
复制
发表时间：
2007-01
期刊：
影响因子：
--
通讯作者：
Dragan Šimović;Mingping Di;V. Marks;D. Chatfield;K. Rein
中科院分区：
文献类型：
--
作者：
Dragan Šimović;Mingping Di;V. Marks;D. Chatfield;K. Rein
研究了三甲基硅基重氮甲烷与α，β-不饱和酯的1，3-偶极环加成反应。所得1-吡唑啉异构化为区域异构2-吡唑啉（a或B）或进行脱甲硅烷基化（c）。丙烯酸酯仅产生B或c。β-取代的亲偶极试剂可以产生所有三种类型的产物。结果表明，2-吡唑啉产物的分布高度依赖于1-吡唑啉中间体上取代基的相对构型。
The 1,3-dipolar cycloaddition of trimethylsilyldiazomethane with alpha,beta-unsaturated esters was examined. The resulting 1-pyrazolines isomerize to regioisomeric 2-pyrazolines (a or b) or undergo desilylation (c). Acrylates yield only b or c. beta-Substituted dipolarophiles may yield all three types of products. This work demonstrates that the distribution of 2-pyrazoline products is highly dependent on the relative configuration of the substituents on the 1-pyrazoline intermediate.