tele Nucleophilic Substitutions of Hydrogen in m-(Trichloromethyl)nitrobenzenes with Cyano and Ester Carbanions
作者:Marek Surowiec、Dimitris Belekos、Mieczysław Mąkosza、George Varvounis
DOI:10.1002/ejoc.200901303
日期:——
Stabilized carbanions of malonates, 2-phenylacetonitrile, or isopropyl 2-phenylacetate add to m-(trichloromethyl)nitrobenzene derivatives to form σ H adducts that lose a chloride ion to give intermediate exo-dichloromethylene nitrocyclohexadienes. These undergo re-aromatization through 1,5-hydrogen shift to yield tele substitution mono adducts. Depending on the stoichiometry of the nitroarene to the
丙二酸酯、2-苯基乙腈或 2-苯基乙酸异丙酯的稳定碳负离子与间(三氯甲基)硝基苯衍生物加成形成 σ H 加合物,该加合物失去氯离子,得到中间体外型二氯亚甲基硝基环己二烯。这些通过 1,5-氢转移进行再芳构化以产生远取代单加合物。取决于硝基芳烃与碳负离子的化学计量,将亲核试剂进一步添加到远单加合物中可以产生双重或三重加合物产物的混合物。在低温下,σ H 加合物在与氯离子消除/1,5-氢转移竞争中进行直接 1,2-加成。