ELECTROPHILIC ADDITION-REACTIONS OF AG+ WITH PT(AUPPH3)82+ AND PT(CO)(AUPPH3)82+ - CRYSTAL-STRUCTURES OF [PT(AGNO3)(AUPPH3)8](NO3)2 AND [PT(CO)(AGNO3)(AUPPH3)8](NO3)2

Pt(AuPPh3)g2+(1) and Pt(CO)(AuPPh3)82+(2) react with Ag+, forming the addition products PtAg(AuPPh3)83+(3) and Pt-(CO)Ag(AuPPh3)83+(4), respectively. Compound 3 is characterized by conductivity measurements, elemental analysis, IR and 31P and 195Pt NMR spectroscopy, and single-crystal X-ray diffraction of its nitrate (monoclinic, space group P2/a, a = 28.007 (18) Å, b = 17.748 (3) Å, c = 28.216 (4) Å, β = 99.12 (3)°, V= 13848 Å3, Z = 4, residuals R = 0.048 and Rw= 0.071 for 3722 observed reflections and 495 variables, Mo KÅ radiation). Compound 4 is characterized by elemental analysis, IR and 31P, 13C, and 195Pt NMR spectroscopy, and single-crystal X-ray diffraction of its nitrate (triclinic, space group Pl, a = 17.4363 (24) Å, b = 20.358 (7) Å, c = 20.500 (3) Å, β = 94.18 (2)°, β = 93.20 (1)°, γ = 99.64 (2)°, V= 7138 Å3, Z = 2, residuals R = 0.065 and Rw= 0.086 for 8383 observed reflections and 475 variables, Mo Kα radiation). In the metal clusters 3 and 4 the central Pt atom is surrounded by eight Au atoms and one Ag atom. The phosphines are attached to the Au atoms, and one nitrate is attached to the Ag atom. CO is μ1-bonded to Pt in 4. Both reactions show the electrophilic addition of a Ag+ion. The alternative synthesis of 4 by addition of CO to 3 shows the amphoteric behavior of the central Pt atom in this cluster compound. © 1990, American Chemical Society. All rights reserved.