A new series of copper(I) complexes of the type [Cu(L)(PPh₃)₂]X (1a-c) and [Cu(L)(dppe)]X (2a-c) have been prepared by the reaction of Cu(MeCN)₄]X (where X = ClO, BF and PF) with N-(2-quinolinylmethylene)-1,5-dimethyl-2-phenyl-1-pyrazole-3-(2H)-one (L) in presence of triphenylphosphine (PPh₃) or 1,2-bis(diphenylphosphino)ethane (dppe) as an ancillary ligand. The UV-visible spectra indicate that, the ancillary phosphine ligands significantly perturb the MLCT state of copper(I) complexes. The thermally stable 1a-c and 2a-c complexes exhibit quasireversible redox behaviour corresponding to Cu(I)/Cu(II) couple. All complexes are tested as catalyst for Sonogashira cross-coupling of phenylacetylene with aryl iodide. The results show that all complexes worked as an effective catalyst at low temperature yielding substituted aryl alkynes as a product. The nature of phosphine ligands and size of counter anions shows marked effect on catalytic properties of all the complexes.

中文翻译：

---

N-（2-喹啉基亚甲基）-1、5-二甲基-2-苯基-1-吡唑-3-（2H）-one和膦作为配体的铜（I）配合物：Sonogashira交叉偶联反应的有效催化剂

新型的[Cu（L）（PPh ₃）₂ ] X（1a-c）和[Cu（L）（dppe）] X（2a-c）型铜（I）配合物已经制备。 （MeCN）₄ ] X（X = ClO ，BF和PF ）与N-（2-喹啉基亚甲基）-1,5-二甲基-2-苯基-1-吡唑-3-（2H）-的反应L）在三苯基膦（PPh ₃）或1,2-双（二苯基膦基）乙烷（dppe）作为辅助配体的情况下。紫外可见光谱表明，辅助膦配体显着干扰了铜（I）配合物的MLCT状态。热稳定的1a-c和2a-c配合物表现出准可逆的氧化还原行为，对应于Cu（I）/ Cu（II）对。测试所有络合物作为苯基乙炔与碘代芳基的Sonogashira交叉偶联的催化剂。结果表明，所有配合物在低温下均作为有效催化剂，产生取代的芳基炔烃。膦配体的性质和抗衡阴离子的大小显示出对所有配合物催化性能的显着影响。