Mechanistic Study on Pd/Mono-N-protected Amino Acid Catalyzed Vinyl-Vinyl Coupling Reactions: Reactivity and E/Z Selectivity
Mechanistic Study on Pd/Mono-N-protected Amino Acid Catalyzed Vinyl-Vinyl Coupling Reactions: Reactivity and E/Z Selectivity
复制标题
Pd/单氮保护氨基酸催化乙烯基-乙烯基偶联反应的机理研究：反应性和 E/Z 选择性
DOI：
10.1021/acs.orglett.6b02542
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发表时间：
2016
期刊：
影响因子：
5.2
通讯作者：
Wu Yun-Dong
中科院分区：
文献类型：
--
作者：
Zhong Xiu-Mei;Cheng Gui-Juan;Chen Ping;Zhang Xinhao;Wu Yun-Dong
报道了Pd/单n保护氨基酸（MPAA）催化的乙烯基-乙烯基偶联反应的质谱和计算相结合的研究。计算研究表明，反应是由苯乙烯的碳氢活化和丙烯酸酯的插入引发的。这得到了质谱分析的支持。MPAA配体通过稳定活性钯催化剂和提供n保护基团作为比醋酸盐更强的碱，促进单取代烯烃之间的交叉偶联反应。在过渡态中，催化剂和底物之间的d−π相互作用更强，从而导致了产物的生成。
A combined mass spectrometric and computational study of the Pd/mono-N-protected amino acid (MPAA)-catalyzed vinyl–vinyl coupling reactions is reported. Computational study reveals that the reaction is initiated by C–H activation of the styrene followed by the insertion of acrylate. This is supported by mass spectrometry. The MPAA ligand facilitates the cross-coupling reaction between monosubstituted alkenes by stabilizing the active palladium catalyst and offering the N-protecting group as a stronger base than acetate. TheE/Zselectivity is attributed to the stronger d−π interaction between the catalyst and the substrate in the transition state leading toEproduct.