β-unsaturated ketones such as 2-benzylideneindan-1-ones, 2-benzylidene-1 -tetralones, 3-benzylidenechroman-4-ones, and 3-benzylidenethiochroman-4-ones induced by a low-valent titanium reagent were studied. Some new spiro compounds were prepared in good yields under neutral and mild conditions. High stereoselectivity was achieved and the stereochemistry of the products was confirmed by X-ray diffraction
α,β-不饱和酮如 2-benzylideneindan-1-ones、2-benzylidene-1-tetralones、3-benzylidenechroman-4-ones 和 3-benzylidenethiochroman-4-ones 的分子间还原环二聚反应对低价
钛试剂进行了研究。一些新的
螺环化合物在中性和温和条件下以高收率制备。实现了高立体选择性,并通过 X 射线衍射分析证实了产物的立体
化学。