Copper(I) complexes supported by a heavily fluorinated bis(pyrazolyl)borate:: syntheses and characterization of [H2B(3,5-(CF3)2PZ)2]CuL (where L = PPh3, NCCH3, HCCPh, H2CCHPh) and {[H2B(3,5-(CF3)2PZ)2]CU}2(1,5-COD)

The fluorinated bis(pyrazolyl)borate [H2B(3,5-(CF3)(2)Pz)(2)](-) allows the isolation of thermally stable copper(I) complexes containing hosphorus and nitrogen based donors, alkyne and alkene ligands. [H2B(3,5-(CF3)(2)Pz)(2)]Cu(PPh3), [H2B(3,5-(CF3)(2)-Pz)(2)]Cu(NCCH3) and {[H2B(3,5-(CF3)(2)Pz)(2)]Cu}(2)(1,5-COD) were synthesized by using [H2B(3,5-(CF3)(2)Pz)(2)]K, CF3SO3Cu, and the appropriate ligand, PPh3, NCCH3 or 1,5-COD. [H2B(3,5-(CF3)(2)Pz)(2)]Cu(HC CPh) and [H2B(3,5-(CF3)(2)Pz)(2)]Cu(H2C = CHPh) were obtained by treating [H2B(3,5-(CF3)(2)Pz) (2)]Cu(NCCH3) with phenylacetylene and styrene, respectively. X-ray data show that [H2B(3,5-(CF3)(2)Pz)(2)]CuL (where L = PPh3, HC CPh, H2C = CHPh) and {[H2B(3,5-(CF3)(2)Pz)(2)]Cu}(2)(1,5-COD) have three-coordinate, trigonal planar copper sites. The bis(pyrazolyl)bo rate moiety adopts the common boat conformation. The v(C C) stretching band of [H2B(3,5-(CF3)(2)Pz)(2)]Cu(PhC CH) was observed at 1927 cm(-1). Structural and spectroscopic data of the alkene and alkyne complexes indicate minimal back-bonding from the d(10) copper(I) center. (c) 2004 Elsevier B.V. All rights reserved.