Synthesis, reactivity and comparative structural studies on copper(I) and gold(I) halo complexes with tripodal polyphosphines in 1:1 metal to ligand ratio. The X-ray crystal structures of three mononuclear neutral compounds

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Cu(I) and Au(I) halides interact with equimolecular amounts of tripodal polyphosphines as CH 3C(CH 2PPh 2) 3(CP 3) in CHCl 3, N(CH 2CH 2PPh 2) 3(NP 3) in CH 2Cl 2 or CH 2Cl 2–S (S=MeOH, Et 2O) and P(CH 2CH 2PPh 2) 3 (PP 3) in CH 2Cl 2 to form Cu(CP 3)X [X=Br ( 1), I ( 2)], [Au 3(CP 3) 2Cl 2]Cl ( 3), [Au 3(CP 3) 3X]X 2 [X=Br ( 4), I ( 5)], Cu(NP 3)X [X=Cl ( 6), Br ( 7), I ( 8)], [Au 2(NP 3) 2]X 2 [X=Cl ( 9), Br ( 10)], Au(NP 3)I ( 11), [Cu 2(PP 3) 2X]X [X=Cl ( 12), Br ( 13)] and [Au 2(PP 3) 2]X 2 [X=Br ( 14), I ( 15)]. Complexes 1, 7 and 11 were shown by X-ray diffraction to consist of neutral monomers with distorted tetrahedral geometry around the metal and the phosphine acting as tridentate chelating ligand. The mass spectra, conductivity measurements and 31P{ 1H} NMR studies for 9 and 10 are indicative of a coexistence with mononuclear forms. Complexes 3, 9 and 14 were also achieved in solution by addition of the appropriate polyphosphine to the compounds Au 3(CP 3)Cl 3 ( 3a), Au 3(NP 3)Cl 3 ( 9a) and Au 4(PP 3)Br 4 ( 14a), respectively, involving ring-closure reactions. Likewise, crystals of 1 were obtained both from solutions of this compound in CH 2Cl 2–EtOH and from solutions in CHCl 3 of ( 1a)·2.5Et 2O ( 1a=Cu 3(CP 3)Br 3). Further additions of the appropriate polyphosphine to 9 and 14 give complexes with new “MP 4” environments and dangling phosphorus that for 14 involve ring-opening processes. By reaction of 3 with CP 3 the complex [Au 3(CP 3) 3Cl]Cl 2, isostructural with 4 and 5, is afforded in solution. The reaction of Cu(CP 3)Cl ( I) with CP 3 followed by 31P{ 1H} NMR seems to occur with retention in part of the starting CuP 3 core and formation of other species containing linear arrangements for Cu(I). No reaction was observed between 6 or 13 and NP 3 or PP 3, respectively.