A Convenient Access to 3-(Trihalomethyl)-3-phenyl-3,4-dihydro-2<i>H</i>-1,4-benzoxazines/thiazines and Chlorinated 3-Phenyl-2,3-dihydro-1,5-benzoxazepines/thiazepines by an Aziridination-Selective-Ring-Opening Sequence
作者:Alexander Khlebnikov、Ekaterina Shinkevich、Mikhail Novikov
DOI:10.1055/s-2006-958938
日期:2007.1
Aziridine ring opening with N-C(1) bond breaking in 1,1-dichloro-1a-phenyl-1a,2-dihydro- 1H-azirino[2,1-c] [ 1,4]benzoxazine and -benzothiazine proceeds under the action of hydrohalo acid to give 3-trihalomethyl derivatives of 1,4-benzoxazine and thiazine. When the same compounds react with boron trifluoride etherate, the ring expansion with N-C(la) bond breaking takes place with formation of 3,4-dichloro-3-phenyl-2
1,1-二氯-1a-苯基-1a,2-二氢-1H-氮丙啶[2,1-c] [1,4]苯并恶嗪和-苯并噻嗪在氮丙啶环的开环作用下进行NC(1)键断裂氢卤酸生成 1,4-苯并恶嗪和噻嗪的 3-三卤甲基衍生物。当相同的化合物与三氟化硼醚合物反应时,发生 NC(Ia) 键断裂的环扩展,形成 3,4-二氯-3-苯基-2,3-二氢-1,5-苯并恶氮杂和 -1, 5-苯并硫氮卓。这些是通过与亲核试剂反应合成 4-取代的 1,5-苯并恶氮杂和 1,5-苯并硫氮杂衍生物的便利前体。