Aspects of nitrile oxide cycloaddition stereoselectivity: Chemistry of 4-cyano-2,2-dimethyl- and 4-cyano-2,2,5,5-tetramethyl-1,3-dioxolane oxides. X-ray structure of (4 , 5)-4,5-bismethoxy-carbonyl-3-[(4)-2,2,5,5-tetramethyl-1,3-dioxolan-4-yl]-Δ2-isox-azoline
作者:Richard H. Jones、Gareth C. Robinson、Eric J. Thomas
DOI:10.1016/0040-4020(84)85117-0
日期:1984.1
4-Cyano-2,2-dimethl- and 4-cyano-2,2,5,5-tetramethyl-1,3-dioxolane oxìdes (1) and (2) were generated from the corresponding chloro-oximes, and trapped by addition to styrene, dimethyl maleate, dimethyl fumarate, and cyclopentene. The additions to styrene and dimethyl fumarate gave 1 : 1 mixtures of diastereoisomeric adducts. However some stereoselectivity was detected in the additions to the -1,2-disubstituted
由相应的氯代肟生成4-氰基-2,2-二甲基-和4-氰基-2,2,5,5-四甲基-1,3-二氧戊环肟(1)和(2),并被捕获除了苯乙烯,马来酸二甲酯,富马酸二甲酯和环戊烯。将苯乙烯和富马酸二甲酯加成,得到非对映异构体加合物的1:1混合物。然而,在-1,2-二取代的烯烃的加成物中检测到一些立体选择性。的结构(4 ,5 )-4,5- bismethoxycarbonyl -3 - [(4 )-2,2,5,5- tetramethyldioxolan -4-基]-Δ 2 -isoxazoline(17)是由一个X-建立射线结构确定。