Mechanistic Studies on the Catalytic Oxidative Amination of Alkenes by Rhodium(I) Complexes with Hemilabile Phosphines
作者:M. Victoria Jiménez、M. Isabel Bartolomé、Jesús J. Pérez-Torrente、Daniel Gómez、F. Javier Modrego、Luis A. Oro
DOI:10.1002/cctc.201200510
日期:2013.1
Cationic rhodium(I) complexes with P,O‐functionalised arylphosphine ligands are efficient catalysts for the regioselective anti‐Markovnikov oxidative amination of styrene with piperidine. The mechanism of the catalytic reaction has been investigated by spectroscopic means under stoichiometric and catalytic conditions. In the presence of piperidine, the catalyst precursor [Rhκ2‐P,O‐Ph2P(CH2)3OEt}2]+
具有P,O-官能化芳基膦配体的阳离子铑(I)配合物是有效的催化剂,用于将哌啶与苯乙烯进行区域选择性的反马氏化学氧化胺化反应。在化学计量和催化条件下,已通过光谱学方法研究了催化反应的机理。在哌啶的存在下,催化剂前体的[Rh κ 2 -P,O--PH 2 P(CH 2)3 OET} 2 ] +(5),得到哌啶络合物的[Rh κ 1 -P-PH 2 P (CH 2)3 OEt} 2(HNC 5 H 10)2] +(8),将其转化为中性酰氨基-哌啶物种的[Rh κ 1 -P-PH 2 P(CH 2)3 OET} 2(NC 5 H ^ 10)(HNC 5 ħ 10)](9)在热条件下。在催化条件下在苯乙烯存在下进行的NMR研究表明,9是苯乙烯催化氧化胺化中的关键物质。有关含环辛二烯-催化剂前体的[Rh(COD)κ 1 -P-PH 2 P(CH 2)3 OET} Ñ] +(n = 1,2)在相