在这项研究中,以高产率合成了一系列不对称的 1,3-二取代苯并咪唑氯化物2a-g,其中两个氮原子被不同的烷基取代,作为 N-杂环卡宾 (NHC) 前体。然后将这些苯并咪唑盐转化为 PEPPSI 家族的相应 Pd-NHC 配合物(PEPPSI = 吡啶增强的预催化剂制备、稳定和引发)3a-g。所有化合物的结构均通过1 H 核磁共振 (NMR) 光谱、13 C NMR 光谱、红外光谱和元素分析进行表征,这些都支持所提出的结构。3c的结构络合物通过 X 射线晶体学测定。通过单晶 X 射线衍射对3c复合物进行了更详细的结构表征,这支持了所提出的结构。Pd-NHC-PEPPSI 配合物用作2-乙酰基呋喃、2-乙酰噻吩和 2-正丙基噻唑与不同芳基溴化物直接 C 5芳基化反应的催化剂。这些配合物表现出中到高的催化活性,并且选择性地位于 C 5位置。此外,还评估了 Pd-NHC-PEPPSI 复合物对一系
NHC–Ag complex derived from N -(1-naphthalenylmethyl)-substituted benzimidazolium salt L12 , affording the corresponding alcohol in 92% yield and with 92% ee. Moreover, the evaluation of an Ir catalyst precursor showed that cationic [Ir(cod) 2 ]BF 4 complex could be used. Furthermore, the introduction of a chiral hydroxyamide side arm into the benzimidazolium salt was critical for the successful design of
Functionalized N-Heterocyclic Carbene Ligands for Dual Enantioselective Control in the Cu-Catalyzed Conjugate Addition of Dialkylzinc Compounds to Acyclic Enones
A series of highly tunable, functionalized azolium compounds have been synthesized from chiral α-amino acid derivatives such as β-amino alcohols or α-amino esters. The combination of a Cu salt and a chiral azolium efficiently facilitated the asymmetric conjugate addition (ACA) reactions of acyclic enones with dialkylzinc under ambient conditions without temperature control. Of the (hydroxy amide)-functionalized
Synthesis, characterization, biological determination and catalytic evaluation of ruthenium(<scp>ii</scp>) complexes bearing benzimidazole-based NHC ligands in transfer hydrogenation catalysis
A new series of ruthenium(II) N-heterocyclic carbene complexes has been synthesized via transmetalation. These complexes are easily handled in very good yields via synthesis of silver–NHC complexes and subsequent reaction with [RuCl2(p-cymene)]2 in dichloromethane (DCM) under argon atmosphere. The newruthenium(II)–NHC complexes were applied to transfer hydrogenation of ketone derivatives using 2-propanol
Rhodium(I) complexes with N-heterocyclic carbene ligands: synthesis, biological properties and catalytic activity in the hydrosilylation of aromatic ketones
catalysts in the hydrosilylation of acetophenone derivatives with triethylsilane at 80 °C for 1 h. These Rh(I) NHC showed good catalytic performance for the hydrosilylation of acetophenone derivatives by using 1 mol % of the rhodiumcomplexes. In addition the new rhodium(I) NHC complexes were tested against MCF7 and MDA-MB-231 cancer cells, Micrococcus luteus LB 14110, Listeria monocytogenes ATCC 19117