Chiral auxiliary-induced stereocontrol in intramolecular Pauson-Khand reactions leading to angular triquinanes
作者:Jordi Tormo、Xavier Verdaguer、Albert Moyano、Miquel A Pericàs、Antoni Riera
DOI:10.1016/0040-4020(96)00844-7
日期:1996.10
thermally induced Pauson-Khand intramolecular cyclization of 1-(3-alkoxy-2-propynyloxy)methylcyclopentenes (2) and 1-(5-alkoxy-4-pentynyl)cyclopentenes (3), derived from chiral secondary alcohols, leads to the tricyclic enones (9) and (10), respectively, in moderate yields and with variable diastereoselectivities. Among the chiral alcohols that we have examined, enynes derived from Oppolzer's 3-(ne
衍生自手性仲醇的1-(3-烷氧基-2-丙炔氧基)甲基环戊烯(2)和1-(5-烷氧基-4-戊炔基)环戊烯(3)的Pauson-Khand分子内热诱导三环烯酮(9)和(10),分别具有中等收率和非对映选择性。在我们研究的手性醇中,衍生自Oppolzer的3-(新戊氧基)异冰片醇4c的烯炔可提供色谱上可分离的非对映异构体,而衍生自10-(甲硫基)异冰片醇4d的烯属化合物以优异的立体控制环化(高达12:1 dr,这是手性辅助立体控制的分子内Pauson-Khand反应迄今记录的最高值之一)。这些结果首次打开了对角三联烷的对映选择性合成的途径,其中三环骨架是从一个单环烯炔以单一步骤立体选择性地构建的,而没有内部立体生成中心。