Allylic Ionization versus Oxidative Addition into Vinyl C−X Bonds by Pd with Polyfunctional Olefin Templates
作者:Eamon Comer、Michael G. Organ、Stephen J. Hynes
DOI:10.1021/ja045416h
日期:2004.12.1
a series of small, olefin-based compounds that were substituted with a variety of allylic and vinylic functional groups was studied. Of particular note, the allylic acetate of 1-acetoxy-2-bromo-2-propene (7) was selectively ionized by Pd in the presence of a malonate nucleophile, while oxidative addition of the C-Br bond to Pd occurred exclusively in the presence of a boronic acid nucleophile. When
研究了 (PPh3)4Pd 催化剂对一系列被各种烯丙基和乙烯基官能团取代的小烯烃基化合物进行活化的化学选择性。特别值得注意的是,在丙二酸亲核试剂的存在下,1-乙酰氧基-2-溴-2-丙烯 (7) 的烯丙基乙酸酯被 Pd 选择性电离,而 C-Br 键与 Pd 的氧化加成仅发生在硼酸亲核试剂的存在。当使用醋酸盐亲核试剂时,醋酸盐离去基团根本没有发生电离,这通过使用氘标记的底物(例如,11)得到证实。该报告表明亲核试剂在底物的催化剂活化之前以某种方式与 Pd 相互作用。当然,在丙二酸亲核试剂的情况下,