Synthesis of 2,5-Dihydro-1,2,4-oxadiazoles through Formal [3 + 2] Cycloaddition of Oxazoles with Nitrosobenzene Derivatives
作者:Hiroyuki Suga、Xiaolan Shi、Toshikazu Ibata
DOI:10.1246/bcsj.71.1231
日期:1998.5
The reactions of substituted oxazoles with nitrosobenzene gave 2-phenyl-2,5-dihydro-1,2,4-oxadiazoles regioselectively through formal [3 + 2] cycloadditions proceeding via a ringopening of oxazoles by an attack of nitrosobenzene. The reactions with 1-chloro- and 1-methyl-4-nitrosobenzenes also produced the corresponding 2,5-dihydro-1,2,4-oxadiazoles regioselectivity.
取代的恶唑与亚硝基苯的反应通过正式的 [3 + 2] 环加成反应区域选择性地得到 2-苯基-2,5-二氢-1,2,4-恶二唑,通过亚硝基苯的攻击使恶唑开环进行。与 1-氯-和 1-甲基-4-亚硝基苯的反应也产生了相应的 2,5-二氢-1,2,4-恶二唑区域选择性。