Dipartimento di Chimica, Università degli Studi di Pavia, Viale Taramelli 12, 27100, Pavia, Italy.
J Org Chem. 2013 Jan 18;78(2):516-26. doi: 10.1021/jo302346a. Epub 2012 Dec 28.
Nitrosocarbonyl intermediates undergo ene reactions with allylic alcohols, affording regioisomeric adducts in fair yields. Nitrosocarbonyl benzene reacts with 3-methyl-2-buten-1-ol and follows a Markovnikov orientation and abstracts preferentially the twix hydrogens over the lone ones. With the more sterically demanding nitrosocarbonyl mesitylene and anthracene, the Markovnikov directing effect is relieved and lone abstraction is observed, affording the 5-hydroxy-isoxazolidines that serve as synthons for the preparation of N,O-nucleoside analogues according to the Vorbrüggen protocol.
亚硝酰基中间体与烯丙醇发生ene 反应，以中等产率得到区域异构体加成物。亚硝酰基苯与 3-甲基-2-丁烯-1-醇反应遵循马氏规则取向，优先选择两个氢而不是孤对氢进行加成。对于更具空间位阻的亚硝酰基均三甲苯和蒽，马氏规则的定向效应得到缓解，观察到孤对氢的加成，得到 5-羟基异恶唑啉，它们可作为根据 Vorbrüggen 方案制备 N,O-核苷类似物的合成子。
