Synthesis and Structural Studies of Tetrahedral [M(Ph2P(CH=CH)PPh2)2]BPh4 and [M(Ph2P(CH2)nPPh2)2]BPh4 (n = 2, 3) Complexes for M = Copper(I), Silver(I), and Gold(I)

Tetraphenylborate salts of the 1 : 2 tetrahedral bis(bidentate) complexes of copper(i), silver(i), and gold(i) with cis-bis(diphenylphosphino)ethene (dppey), [M(Ph2PCH=CHPPh2)2]BPh4, cis-bis(diphenylphosphino)ethane (dppe), and cis-bis(diphenylphosphino)propane (dppp), [M(Ph2P–R–PPh2)2]BPh4 (R = (CH2)2, (CH2)3), have been prepared and characterized by NMR spectroscopy, electrospray mass spectrometry, and single crystal X-ray structural analysis at 200 K. Structures of the dppey complexes as acetone solvates show the Cu and Ag complexes to be isostructural with the previously reported Au complex, crystallizing in space group P 21/n with a ~ 25.5, b ~ 15.6, and c ~ 34.2 Å, and β ~ 103°. Structures of the dppe complexes show the copper complex to crystallize in the chiral space group P21 with a 11.8954(5), b 20.1904(5), and c 14.8999(5) Å, and β 111.366(5)°. The Ag and Au complexes are isostructural, crystallizing in space group P21/c with a ~ 17.8, b ~ 17.6, and c ~ 20.9 Å, and β ~ 107°. Structures of the dppp complexes show the copper complex to crystallize in space group P21/c with a 17.8399(4), b 19.8803(4), and c 18.7165(3) Å, and β 102.197(2)°. The Ag and Au complexes are isostructural, crystallizing in space group P21/n with a ~ 17.7, b ~ 18.6, and c ~ 19.6 Å, and β ~ 100°. Across the three series of complexes, the M–P bond lengths increase in the order Cu < Au < Ag with Cu–P = 2.281(3)–2.314(1) Å, average 2.30(1) Å; Au–P = 2.363(1)–2.4322(8) Å, average 2.40(2) Å, and Ag–P = 2.445(1)–2.5303(5) Å average 2.49(2) Å.