Pd-Catalyzed Allylic Isocyanation: Nucleophilic N-Terminus Substitution of Ambident Cyanide
Pd-Catalyzed Allylic Isocyanation: Nucleophilic N-Terminus Substitution of Ambident Cyanide
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Pd 催化的烯丙基异氰化：环境氰化物的亲核 N 端取代
DOI：
10.1021/acscatal.9b00858
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发表时间：
2019
期刊：
影响因子：
12.9
通讯作者：
Ohkuma Takeshi
中科院分区：
文献类型：
--
作者：
Yurino Taiga;Tani Ryutaro;Ohkuma Takeshi
在催化量Pd(OAc)2存在下，烯丙基磷酸盐与三甲基硅基氰化物(TMSCN)反应生成相应的烯丙基异腈。没有观察到在传统的Pd(0)催化反应中选择性生成的烯丙基腈。使用磷酸盐作为离开基团，对于实现作为末端亲核试剂的氰化物物种的完全区域选择性是至关重要的。该反应适用于一系列芳香族、杂芳族、乙烯基和脂肪族取代的烯丙基磷酸盐。机理研究表明，烯丙基异氰化是由Pd(II)物种催化的，而不是由Pd(0)催化的。
In the presence of catalytic amount of Pd(OAc)2, allylic phosphates reacted with trimethylsilyl cyanide (TMSCN) to afford the corresponding allylic isonitriles exclusively. No allylic nitriles, which are selectively obtained in the traditional Pd(0)-catalyzed reaction, were observed. The use of phosphate as the leaving group was crucial to achieve complete regioselectivity of the ambident cyanide species as theN-terminus nucleophile. The reaction was applicable to a series of aromatic-, heteroaromatic-, vinylic-, and aliphatic-substituted allylic phosphates. The mechanistic studies suggested that the allylic isocyanation was catalyzed by the Pd(II) species, and not by Pd(0).