The electron-transfer-catalyzed rearrangement of the annelated housane 4a on treatment with tris(p-bromophenyl)aminium hexachloroantimonate (TBA(*)(+)SbCl(6)(-)) affords regioselectively the two isomeric olefins endo-5a and 6a by 1,2 migration of the two groups at the methano bridge. Acid-catalyzed rearrangement gives in addition to endo 5a and 6a also the regioisomer endo-7a as major product. The
用三(对-
溴苯基)六氯
锑酸
铵(TBA(*)(+)SbCl(6)(-))处理后的退火过的粗麻烷4a的电子转移催化重排提供了区域选择性的两种异构烯烃endo-5a和6a在甲基桥上,两个基团的1,2迁移。酸催化的重排除产生内切5a和6a外,还产生区域异构体endo-7a作为主要产物。重排产物endo-5a和6a的形成都表明自由基阳离子和碳阳离子中间体的平面构象。通过在自由基阳离子和碳阳离子中间体中的重排末端处的取代基使自由基对阳离子位点电子稳定,可以合理地调节区域选择性。出于准备目的而感兴趣的