A highly stereoselective C-C bond-forming reaction was achieved. In the presence of titanium tetrahalides, reaction of conjugated enynes, α-ethynyl-α′-methoxycarbonyl ketene-S,S-acetals, with aldehydes gave (E,Z)-3,7-dihalo-3,6-dienedioates in good to high yields. A mechanism for the C-C bond-forming reaction is detailed and considered to be a concerted process.
实现了高度立体选择性的 C-C 键形成反应。在四卤化
钛存在下,共轭烯炔、δ-
乙炔基-δ′-甲氧羰基烯酮-S,S-
乙醛与醛反应生成了(E,Z)-3,7-二卤-3,6-二烯二酸酯,收率从好到高。详细介绍了 C-C 键形成反应的机理,并认为这是一个协同过程。