Neutron diffraction analysis of [H3Pt2(Ph2PCH2CH2PPh2)2]+[BPh4]-: an unusual example of an unsymmetrical [P2Pt(.mu.-H)2PtP2H] core

Abstract

compound K[NEt4] [Con(SC10H13)4]. The reaction of 2 equiv of LiSC10H13 with CoCl2 in ethanol or CH3CN gives a light green precipitate whose elemental analysis is consistent with a Co(SC10H13)2 formulation.14 This compound is insoluble in alcohols, CH3CN, hexane, and toluene but is soluble in DMF to give blue-green solutions.The average Co-S bond length in 1 (2.28 (1) Á) is 0.03 Á shorter than the corresponding distance in 13 The difference in the overall charge on the anions is principally responsible for the discrepancy in these parameters.2,3 Also, the differences in the Co-S-Ph conformation may contribute to the change in the bond distances. In 1 the Co-S bonds are approximately orthogonal to plane of the durene ring, while in Co(SPh)42-the Co-S bonds lie in the plane determined by the phenyl rings.13 The bond angles of the CoS3N unit show large deviations from the normal tetrahedral angle of 109.5°; these deviations result from the mixed-ligand coordination and the steric interactions among the ligands.White crystals of [N(n-Pr)4][Cu(SC10H13)2] (2) are obtained in 60% yield from the cooled filtrate of the room-temperature reaction of 1 equiv of Cu(CH3CN)4BF4 and [N(n-Pr)4]Br with 3 equiv of LiSC10H13 in ethanol. The linear digonal coordination of the copper was revealed by an X-ray crystal structure determination (Figure 2).15 The anion has crystallographic C2 symmetry with the S-Cu-S' angle equal to 178.6 (1)°. The Cu-S distance of 2.137 (2) A is substantially shorter than the average Cu-S distance in the three-coordinate copper in [Ph4P]2[Cu(SPh)3]8 and slightly less than average Cu-S distance for the two-coordinate coppers in [Cu5(SPh)7]2-and [Cu5(S-Z-Bu)6]-.9,10 The observed large change in the Cu-S distance as a function of coordination number should be a valuable consideration in the interpretation of EXAFS data of copper proteins.16A benzenethiolate complex, (PPh4)[Cu(SPh)2], which is analogous to 2, was previously reported but was not structurally characterized.8 [Cu(SPh)2]-differs from 2 in that it readily undergoes oligomerization reactions to give the cluster compounds [Cu4(SPh)6]2-and [Cu5(SPh)7]2-.8,9,11 The reaction of Cu(I) salts with C10H13S" was studied for a variety of Cu/SR ratios (5/1 to 1.5/1) and under different reaction conditions; 2 was the only isolated product, and in no case was the yellow color, which is characteristic of many Curx(SR)y cluster complexes,8-11 ever detected.The reduced tendency of 2,3,5,6-tetramethylbenzenethiolate to bridge metal centers makes it an attractive ligand for the synthesis and study of monomeric metal thiolate complexes in cases where less sterically demanding ligands give clusters or polymeric compounds.17,18

Structure of the dinuclear platinum monohydrido bridged complex [(PEt3)2HPt(μ-H)PtH(PEt3)2][BPh4]

“…Often the hydrido bridges are accompanied by other bridging atoms or groups such as phosphides and carbon monoxide. Among this type of dinuclear compound, a few trihydridodiplatinum systems have been studied: those containing bridging phosphines [PhEPCHEPPh2 (Brown, Puddephatt, Rashidi & Seddon, 1977)], chelating phosphines [(t-Bu)EPCHECHEP(t-Bu)2 (Tulip, Yamagata, Yoshida, Wilson, Ibers & Otsuka, 1979) and Ph2PCHECHEPPh2 (Minghetti, Bandini, Banditelli & Bonati, 1977;Chiang, Bau, Minghetti, Bandini, Banditelli & Koetzle, 1984)] and monodentate phosphines [-PEt3, PPh3 and PCy3 (Bracher, Grove, Pregosin & Venanzi, 1979;Bachechi, Bracher, Grove, Kellenberger, Pregosin, Venanzi & Zambonelli, 1983)]. …”

Synthesis, Structure, and Electronic Properties of Monomeric and Dimeric Trispyrazolylborate Platinum(II) Hydride Complexes

“…1,2 A large group of dimeric platinum complexes with bridging hydride ligands contains the [Pt 2 H n P 4 ] m+ (n ) 1-3; m ) 1,2) core (e.g., B-D in Figure 1). These compounds are doubly hydride bridged and stabilized by monophosphine [3][4][5][6][7] or diphosphine ligands [8][9][10][11][12][13][14][15] or else they are singly hydride bridged and again stabilized by monophosphine [16][17][18][19][20] or diphosphine ligands. [21][22][23] Spencer's dimeric complexes containing the [Pt 2 H 2 (P∩P) 2 ] 2+ core (C in Figure 1), 14,15 which are yellow or red, are particularly relevant since they are direct analogues of the dicationic, N-supported dihydride-bridged dimer reported in this paper.…”

Organodiphosphines in Pt(II) coordination complexes

“…Inspection of the data of dimeric derivatives reveals that the Pt Pt bond distances range from 2.698 114 to 2.980 Å 120 (ave 2.785 Å), and Pt····Pt distance range from 3.059 138 [114][115][116] and PtP 3 Cl + PtCl 2 P 2 . 132 There are four categories of Pt P (organodiphosphine) bond distances, the mean distances increase in the order: 2.270 Å (chelated) < 2.290 Å (bridged) < 2.322 Å (trans to C) < 2.348 Å (trans to H).…”

“…These chelated ligands are unsymmetrically coordinated to the Pt(II) atom with the Pt P bond distances of 2.262 and 2.346 Å. The Pt-H bond distances are not available.There are four dimeric species,[(η 2 -dchpp)Pt(μ-H) 2 Pt(η 2 -dchpp)](BF 4 ) 2 , 114 [(η 2 -dchpp)Pt(μ-H) 2 Pt(η 2 -dchpp)](BF 4 ) 2 , 114 [(η 2 -dppe)Pt(μ-H) 2 Pt(η 2 -dppe)(H)]BPh 4 , 115 and [(η 2 -dppm)Pt(μ-H) 2 Pt(η 2 -dppm)(H)]BPh 4 ,116 in which pairs of H atoms serve as bridges -in Mole et al114 between the two Pt(η 2 -PL) moieties and in Chiang et al115 and Knobler et al 116 between (Pt(η 2 -PL) and Pt(η 2 -PL)(H) units. The mean Pt Pt bond distance is 2.716 Å (range 2.698(1) to 2.728(1) Å).…”