Regioselective Preparation of Allylic Sulfones by Palladium-Catalyzed Reactions of Allylic Nitro Compounds with Sodium Benzenesulfinate
作者:Noboru Ono、Isami Hamamoto、Takashi Kawai、Aritsune Kaji、Rui Tamura、Masato Kakihana
DOI:10.1246/bcsj.59.405
日期:1986.2
thermodynamically-stable isomers is negligible. On the other hand, the palladium-catalyzed sulfonylation of allylic acetates with sodium benzenesulfinate is accompanied by the isomerization to give the thermodynamically-controlled products selectively. These results can be explained by assuming that allylic nitro compounds are more reactive to the palladium catalyst than allylic acetates and sulfones.
在 N,N-二甲基甲酰胺 (DMF) 中 5 mol% Pd(PPh3)4 存在下,在 20–70 °C 下,用苯亚磺酸钠处理烯丙基硝基化合物 1–10 小时,导致形成占优势的烯丙基砜动力学控制的产品。产物分布主要受烯丙基单元取代基的电子性质控制,异构化为热力学稳定的异构体可以忽略不计。另一方面,钯催化的乙酸烯丙酯与苯亚磺酸钠的磺酰化伴随异构化,选择性地得到热力学控制的产物。这些结果可以通过假设烯丙基硝基化合物比烯丙基乙酸酯和砜对钯催化剂更具反应性来解释。