Novel [1,<i>N</i>]-Carbon to Carbon Rearrangement of an Ester Group via Organotitanium Intermediates Wherein the<i>N</i>Varies from 2 to 5. Full Scope and Limitation Leading Predominantly to the Rearrangement
作者:Takanori Yamazaki、Hirokazu Urabe、Fumie Sato
DOI:10.1246/bcsj.71.1673
日期:1998.7
Malonates and methanetricarboxylates having an unsaturated side chain such as 2, 12, 20, 22, 24, 31, or 37 underwent a new ester rearrangement reaction promoted by (η2-propene)Ti(O-i-Pr)2 to afford the succinate derivative 4 or α,β-unsaturated ester 17, 21, 23, 25, 34, or 38 via the migration of the ester group from its original bis- or tris-ester position to the acetylene- or olefin-titanium complex
具有不饱和侧链如 2、12、20、22、24、31 或 37 的丙二酸酯和甲三羧酸酯在 (η2-丙烯)Ti(Oi-Pr)2 的促进下进行新的酯重排反应,得到琥珀酸酯衍生物 4或 α,β-不饱和酯 17、21、23、25、34 或 38,通过酯基团从其原始双-或三-酯位置迁移到乙炔-或烯烃-钛络合物。已经发现与所需迁移竞争的副反应是酯侧链的脱烷基化和简单的环化。确定了允许酯迁移优先路径的底物和条件以及该反应的范围和限制。