Development of a Palladium‐Catalyzed Process for the Synthesis of Z‐Alkenes by Sequential Sonogashira–Hydrogenation Reaction

Abstract

A novel and selective sequential one‐pot protocol for the synthesis of Z‐alkenes via Sonogashira–semihydrogenation is reported. The efficiency of the methodology is increased by utilizing PdCl2/BuPAd2 as homogeneous catalyst for the Sonogashira coupling and subsequently transforming the transition metal complex into a heterogeneous Pd hydrogenation catalyst. This methodology represents one of the rare examples directly combining homogeneous and heterogeneous catalysis.

Z∶E Selective Preparation of Disubstituted Internal Alkenes and Trisubstituted Alkenes

“…E/Z = 100:nd over-reduced = nd 图式 10 钯催化的配体调控炔烃的选择性氢化反应 Scheme 10 Palladium-catalyzed ligand regulating selective hydrogenation of alkynes Reproduced from Ref. [43] with permission from John Wiley and Sons 同年, Beller 课题组 [44] 提了一种新的钯催化的合成 Z-烯烃 34 的新方法, 在催化过程中钯金属既可以作为 均相催化剂, 也可作为多相加氢催化剂. 该方法包括三 个步骤: 钯催化的均相 Sonogashira 反应, 均相钯配合物 的非均相化, 选择性半氢化反应, 其中 Z∶E＞91∶9.…”