A platinum cluster complex containing a triply bridging carbonyl. The synthesis and structure of (.mu.3-carbonyl)tris[.mu.-bis(diphenylphosphino)methane]-triangulo-triplatinum(2+) hexafluorophosphate

Abstract

Reaction of [PflC^CCF^dppm)], dppm = Ph2PCH2PPh2, with CO in aqueous methanol gives the cluster complex [Pt3(/u3-CO) (ju-dppm)3] [CF3C02] 2 (1) which may be converted to the [PFe]" salt 2. The complexes 1 and 2 are the first complexes reported to contain the Pt3U3-CO) group and are significant as models for CO chemisorbed at a threefold site on a Pt surface. Complexes 1 and 2 were characterized by elemental analysis, IR, and , 31P, and 196Pt NMR and by X-ray crystallography (for 2, as the acetone solvate). Crystals of 2-C3H60 are triclinic, space group PI, with Z = 2, a = 14.090 (2) A, b = 22.711 (4) A, c = 13.637 (4) A, a = 103.43°, ß = 99.52 (2)°, and y = 106.72 (1)°. The structure was solved by the heavy-atom method and refined by full-matrix least-squares calculations with anisotropic thermal parameters for the non-phenyl and non-solvate atoms. At convergence, R = 0.035 for 6234 reflections with I > 3 ( ). The crystal structure contains discrete cations, anions, and acetone solvate molecules. The Pt atoms of the cation form a triangle with Pt-Pt = 2.613-2.650 (1) A. The carbonyl ligand occupies a triply bridging site with Pt-C = 2.080-2.095 (9) A. The atoms of the Pt3P6 moiety are only approximately coplanar; the Pt-P distances are in the range 2.262-2.304 (2) A. The three Pt2P2C five-membered rings adopt envelope conformations with the CH2 moiety at the flap.

Photoinduced oxidative degradation of unsaturated M3(dppm)3CO2+ clusters (M = Pd, Pt) by chlorocarbons and chloride ion

“…Materials [Pd,(d~pm)~COl(Y = CF3C02,PF6), (7) and [Pt3(dppm),COl-(PF6)2 (8) were prepared according to literature procedures. Methanol (BDH), dichloromethane (BDH), chloroform (BDH), carbon tetrachloride (Anachemia), sodium chloride (Fisher), benzyl chloride (Aldrich Chem.…”

“…cluster as demonstrated by Puddephatt and co-workers (7,8). The following experiments are performed: (i) measurements of in the presence of CO(g), and (ii) measurements of for the P F 6 and CF3C02-salts.…”

New trimetallic sandwich complexes of platinum(0) and palladium(0)

“…Analysis of the X-ray data showed that the central triplatinum motif in 1 is an almost equilateral triangle with PtePt distances of 2.7361(5), 2.7461(7) and 2.7135(7) Å ( Table 2). The PtePt distances are significantly longer than those reported for other triangular triplatinum complexes synthesized by Puddephatt and coworkers [14,15]. In general, the structure of 1 is analogous to the structure of The internal PtePt distances in 2 are only marginally longer than those observed in 1, however the Pt-halide distances (1, X ¼ Cl; 2 X ¼ Br) were longer in 2 as expected for the heavier halogen atoms, and similar to those observed in the palladium analog.…”

Unexpected Reaction of the Unsaturated Cluster Host and Catalyst [Pd3(μ3‐CO)(dppm)3]2+ with the Hydroxide Ion: Spectroscopic and Kinetic Evidence of an Inner‐Sphere Mechanism

“…The kinetics were resolved by means of stoppedflow experiments and are consistent with the proposed mechanism. In the presence of an excess of Bu 4 NOH, an electrocatalytic process was observed with modest turnover numbers (7)(8).…”

“…Since the first report on the synthesis and characterisation of the [Pd 3 n + throughout this manuscript in which n = 0, 1, 2; dppm = bis-A C H T U N G T R E N N U N G (diphenylphosphino)methane) in the 1980s, by Puddephatt et al, [1][2][3] and its Pt analogue, [4] numerous and exhaustive studies on its reactivity and properties have appeared in the literature. [5][6][7][8][9][10] This cluster exhibits a triangular Pd 3 (M 3 ) centre with three dppm-supported M À M single bonds.…”