N-Heterocyclic carbene catalyzed intramolecular crossed aldehyde–ketone benzoin condensation in the chalcone of o-phthalaldehyde: a facile synthesis of naphthalenones
作者:Shravankumar Kankala、Ravikrishna Edulla、Sarangapani Modem、Ravinder Vadde、Chandra Sekhar Vasam
DOI:10.1016/j.tetlet.2011.05.070
日期:2011.7
The intramolecular crossed aldehyde–ketone benzoin condensation in the chalcone of o-phthalaldehyde (OPA) catalyzed by N-heterocyclic carbene (NHCs) generated in situ from readily available imidazolium and thiazolium salts is described. In this reaction, bicyclic α-hydroxyl ketones (naphthalenone type tertiary alcohol) were selectively produced in good yields (75–94%) in shorter reaction times (20 min)
描述了由易得的咪唑鎓盐和噻唑鎓盐原位生成的N杂环卡宾(NHC)催化邻苯二甲醛(OPA)查耳酮中的分子内交叉醛-酮安息香缩合。在此反应中,通过在UPA-查耳酮(雷焦)中亲和添加了由umpolung生成的酰基阴离子,在较短的反应时间(20分钟)内有选择地以良好的收率(75-94%)以高收率(75-94%)选择性地生产了双环α-羟基酮(萘醌型叔醇)。受控)。