Oxidation of Heteroleptic Diarylpalladium Compounds with <i>tert</i>-Butyl Hydroperoxide. Substituent Effects in Aromatic Oxidation Reactions
作者:Jean-Marc Valk、Jaap Boersma、Gerard van Koten
DOI:10.1021/om960386f
日期:1996.10.15
A series of heteroleptic diarylpalladium compounds, containing both a naphthyl (1-C10H6CH2NMe2-2 or 1-C10H5CH2NMe2-2-Me-3) and a phenyl (1-C6H4CH2NMe2-2 or 1-C6H3CH2NMe2-2-Me-x, x = 3, 5, 6) monoanionic C,N-bidentate ligand, was reacted with tert-butyl hydroperoxide (TBHP) to give selective oxygen insertion into one of the C−Pd bonds. It was found that the order of reactivity of the palladium−carbon
一系列杂芳基二芳基钯化合物,包含萘基(1-C 10 H 6 CH 2 NMe 2 -2或1-C 10 H 5 CH 2 NMe 2 -2-Me-3)和苯基(1-C 6 H 4 CH 2 NMe 2 -2或1-C 6 H 3 CH 2 NMe 2 -2-Me- x,x = 3,5,6)单阴离子C,N-双齿配体与叔反应-丁基过氧化氢(TBHP)使氧选择性插入C-Pd键之一。发现钯-碳键的反应性顺序以1-萘基-Pd>苯基-Pd的顺序降低。甲基的取代基的引入,使我们能够微调氧化反应(的区域选择性我。Ë。苯基的比例相对于萘氧合受到影响),但不扭转的顺序。甲基对包含它们的芳族底物具有减活作用,表明在实际的氧化步骤中氧化诱导的亲核途径。单加氧产物RPdOR'的产率从82%到97%不等,与VO(acac)2或[RhCl(cod)]的存在无关。尽管在这些催化剂的存在下反应速率大大提高,但是在图2的催化剂中反应速率却大大提高。