Secondary amine-catalyzed [3 + 3] benzannulation to access polysubstituted benzenes through iminium activation
作者:Lin Jiang、Hang Li、Jiang-Feng Zhou、Ming-Wei Yuan、Hong-Li Li、Yong-Ming Chuan、Ming-Long Yuan
DOI:10.1080/00397911.2017.1402351
日期:2018.2.1
ABSTRACT An organocatalytic [3 + 3] benzannulation to access polysubstituted benzenes from readily available α,β-unsaturated aldehydes and 1,3-bis(phenylsulfonyl)propene or 4-sulfonylcrotonates is described. The key reaction step is considered to be the iminium activation of enals by a secondary aminocatalyst. This organocatalytic protocol avoids the traditional strategy which is always with the aid
摘要描述了一种有机催化 [3 + 3] 苯并环化,以从容易获得的 α,β-不饱和醛和 1,3-双(苯磺酰基)丙烯或 4-磺酰基巴豆酸酯中获得多取代苯。关键反应步骤被认为是仲氨基催化剂对烯醛的亚胺活化。这种有机催化方案避免了总是借助过渡金属或化学计量量的强碱的传统策略,并允许以高到极好的收率(74-96%)合成三取代苯。图形概要