Copper(I) Isocyanide and Phosphane Complexes of Fluorinated Mono‐ and Bis(pyrazolyl)borates

New copper(I) complexes have been synthesized from the reaction between [Cu(CH3CN)4]PF6 or CuI, triphenylphosphane, tert-butyl isocyanide or cyclohexyl isocyanide co-ligands, and the fluorinated pyrazolylborate ligands sodium trihydro[5-(trifluoromethyl)pyrazol-1-yl]borate and potassium dihydrobis[3-(trifluoromethyl)pyrazol-1-yl]borate. These compounds have been characterized by elemental analysis, FT-IR and multinuclear (1H, 13C, 19F and 31P) NMR spectroscopy, and ESI mass spectrometry. The solid-state structure of [{H3B[5-(CF3)pz]}Cu(PPh3)2] is also reported. This complex features a κ2N,H-bonded trihydro(pyrazolyl)borate ligand, a rare Cu–HB bond, and a distorted, pseudo-tetrahedral copper atom with a large P–Cu–P angle. The solid state structures of [{H2B[3-(CF3)pz]2}Cu(CNtBu)2] and [{H2B[3-(CF3)pz]2}Cu(CNCy)2], which have pseudo-tetrahedral copper sites, are also reported. The bis(pyrazolyl)borate ligand in these complexes acts as a κ2N,N′ donor and adopts a flattened boat conformation. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)