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,