Cu(I) complexes bearing the new sterically demanding and coordination flexible tris(3-phenyl-1-pyrazolyl)methanesulfonate ligand and the water-soluble phosphine 1,3,5-triaza-7-phosphaadamantane or related ligands

The new sterically hindered scorpionate tris(3-phenylpyrazolyl)methanesulfonate (Tpms(Ph))(-) has been synthesized and its coordination behavior toward a Cu(I) center, in the presence of 1,3,5-triaza-7-phosphaadamantane (PTA), N-methyl-1,3,5-triaza-7-phosphaadamantane tetraphenylborate ((mPTA)BPh4]) or hexamethylenetetramine (HMT) has been studied. The reaction between Li(Tpms(Ph)) (1) and Cu(MeCN)4]PF6] yields Cu(Tpms(Ph))(MeCN)] (2) which, upon further acetonitrile displacement on reaction with PTA, HMT, or (mPTA)BPh4], gives the corresponding complexes Cu(Tpms(Ph))(PTA)] (3), Cu(Tpms(Ph))(HMT)] (4), and Cu(Tpms(Ph))(mPTA)]PF6] (5). All the compounds have been characterized by (1)H, (31)P, (13)C, COSY or HMQC-NMR, IR, elemental analysis, and single crystal X-ray diffraction. In the complexes (3) and (5), which bear a phosphine ligand (i.e., PTA and mPTA, respectively), the new scorpionate ligand shows the typical N, N, N-coordination mode, whereas in (2) and (4), bearing a N-donor ligand (i.e., MeCN and HMT, respectively), it binds the metal via the N,N,O chelating mode, involving the sulfonate moiety.