Versatile Pd-Catalyzed CH Oxidative Cyclization of Homoallylhydrazones to Pyrazolines and Tetrahydropyridazines
作者:Cleve Dionel Mboyi、Ibrahim Abdellah、Carine Duhayon、Yves Canac、Remi Chauvin
DOI:10.1002/cctc.201300220
日期:2013.10
Pd‐catalyzed 5‐exo‐trig or 6‐endo‐trig CH oxidative cyclization of C‐homoallyl‐N‐sulfonylhydrazones to 5‐vinylpyrazolines or 6‐methylidene‐1,4,5,6‐tetrahydropyridazines, respectively, is shown to be controlled in a highly selective manner by the ionic character of the PdII catalytic center. This character is ultimately defined by the nature of the X ligand in the PdX2 salt serving as an in situ precursor
Pd催化的5-外型-三角函数或6-内- TRIG Ç ħ氧化环化Ç -homoallyl- Ñ -sulfonylhydrazones到5- vinylpyrazolines或6-亚甲基-1,4,5,6- tetrahydropyridazines分别示出通过Pd II催化中心的离子特性以高度选择性的方式进行控制。此特性最终由PdX 2盐中的X配体的性质定义,该X配体是涉及BIPHIMIP 2-(二苯基膦基)-1- [2-(二苯基膦基)苯基] -1 H的活性催化物质的原位前体咪唑}是这两种方法的最佳观众二膦配体。乙酸盐(X = OAc)有利于6-内酯法,而非配位阴离子,如甲苯磺酸盐和三氟甲磺酸盐(X = OTs,OTf)则有利于5- exo法。