A highly active and regioselective catalyst obtained from a novel dicationic ligand (1) and Rh(CO)2(acac) for hydroformylation of 1-hexene and 1-octene in ionic liquids is reported. Optimisation studies of various reaction parameters led to an unprecedentedly active (TOFs > 6200 mol mol−1 h−1, T
= 100 °C), selective (l/b ratios > 40) and stable hydroformylation procedure. No catalyst leaching (Rh-loss < 0.07% of initial rhodium intake, P-loss < 0.4% of the initial phosphorus intake) or losses in performance could be measured during 1-octene hydroformylation recycle experiments in 1-butyl-3-methylimidazolium hexafluorophosphate. At low catalyst loadings activities and regioselectivities competitive with one-phase catalysis in conventional solvents were observed. At high catalyst loadings the system is extremely stable and has a long shelf-life as a result of the formation of stable, if inactive rhodium dimers.
catalysis: homogeneous
报道了一种由新型双阳离子
配体 (1) 和 Rh(CO)2(acac) 获得的高活性和区域选择性催化剂,用于
离子液体中
1-己烯和 1-
辛烯的加氢甲酰化。各种反应参数的优化研究导致了前所未有的活性(TOF > 6200 mol mol−1 h−1,T
= 100 °C)、选择性(l/b 比 > 40)和稳定的加氢甲酰化过程。在 1-
辛烯加氢甲酰化循环实验中,在
1-丁基-3-甲基咪唑六氟磷酸盐中,未测量到催化剂浸出(Rh 损失 < 初始铑摄入量的 0.07%,P 损失 < 初始磷摄入量的 0.4%)或性能损失。在低催化剂负载量下,观察到与传统溶剂中的一相催化相媲美的活性和区域选择性。在高催化剂负载量下,该系统极其稳定,并且由于形成稳定的(即使是非活性的)
铑二聚体而具有较长的保质期。
催化:均相