Titanocene(II)-Promoted Multicomponent Reactions Utilizing Alkynyl Sulfones, Alkenyl Sulfones, and Carbonyl Compounds: A Novel Method for the Synthesis of Vinylallenes
作者:Akitoshi Ogata、Masami Nemoto、Kenji Kobayashi、Akira Tsubouchi、Takeshi Takeda
DOI:10.1002/chem.200601326
日期:2007.1.22
Titanocene(II)-promoted cross coupling of alkynyl- and (Z)-alkenyl sulfones affords alpha-(phenylsulfonyl)alkenyltitanium species. Further treatment of these species with the titanocene(II) reagent generates titanium vinylvinylidene complexes, which react with carbonyl compounds in one pot to produce substituted vinylallenes with complete stereoselectivity. By using alpha,beta-unsaturated ketones,
钛茂金属(II)促进的炔基和(Z)-烯基砜的交叉偶联提供了α-(苯磺酰基)烯基钛物种。用钛茂(II)试剂对这些物质进行进一步处理,生成乙烯基乙烯基亚乙烯基钛配合物,该配合物在一个罐中与羰基化合物反应生成具有完全立体选择性的取代的乙烯基烯丙基。通过使用α,β-不饱和酮,还可以立体选择性地获得1,3,4,6-四烯。