John P. Fackler

Sulfur chelates 36. Structural characterization of the Trans isomers of the O-ethylphenyldithiophosphonates of Pd(II) and Pt(II), M[S2P(OC2H5)C6H5]2. Cis-Trans isomerization of the planar Pd(II) complex

Abstract Ni(II), Pd(II) and Pt(II) complexes of O-ethylphenyldithiophosphate, [S2P(OEt)C6H5]−, crystalize as trans products although the MS4 coordination about the metal is square planar. Isomerization occurs in organic solvents to produce essentially (by NMR) equal amounts of cis and trans isomers. The rate of isomerization decreases Ni ⪢ Pd > Pt. The isomerization of trans-Pd[S2P(OEt)C6H5]2 has been studied quantitatively in various solvents. In benzene Ea ≅ 18 kcal/mole with ΔHDG ≅ 18 kcal/mole and ΔS‡ ≅ −17 e.u. The rearrangement appears to be solvent assisted. CS2 increases the isomerization rate by a factor of five. The X-ray crystal structures of the Pd(II) and Pt(II) complexes are described in detail. The MS distances are approximately 2.34 A in both complexes, although the space groups are different.

Sulphur chelates 33. Preparation, characterization and x-ray structure determination of (chloro)(pentane-2,4-dithionato)(triethylphosphine)nickel(II), Ni(SacSac)(PEt3)Cl, an asymmetric complex which displays fluxional behavior in solution on the NMR time scale

Abstract The tittle compound has been prepared and characterized spectroscopically and by single-crystal X-ray crystallography (refined to R1 = 0.052, Rw = 0.064 with 1837 data having I > 3σ(I)). The dithioacetylacetonate (SacSac) methyl groups are NMR equivalent at room temperature, but can be resolved at temperatures below 288 K. The compound crystallizes in the monoclinic space group P21/n with a = 7.6107(3) A, b = 18.1466(28) A and c = 11.5270(5) A; β =98.459(3)°, V = 1574.12(25) A3, and Z = 4. The coordination about the nickel(II) is planar. Important nickelligand lengths are NiS (trans Cl) 2.108(2) A, NiS (trans P) 2.154(2) A, NiCl 2.206(2) A, NiP 2.232(2) A with angles SNiS 97.9(1)°, SNiCl 85.Cl 85.6(1)°, SNiP 91.4(1)° and ClNiP 85.2(1)°. Two of the triethylphosphine ethyl groups lie in a plane approximately normal to the rest of the molecule. The dithioacetylacetonate dimensions are similar to those in Ni(SacSac)2, although the chelate bite is smaller, and there may be some asymmetry in the CS bonding in Ni(SacSac)PEt3Cl. The molecules pack with their chelate rings approximately parallel.

Sulfur Chelates 29. Ni(II), Pd(II), Pt(II), Co(III) and Cu(I,II) Complexes of O-Phenyldithiocarbonates

Abstract The synthesis and characterization of metal aryl xanthates (O-aryldithiocarbonates) of Ni(II), Pd(II), Pt(II), Co(III), Tl(I), K(I) and Cu(I,II) are described. It has been shown that thallium(I) phenoxides, except with very acidic phenols such as p-bromophenol, add CS2 in hydrocarbon solvents. The thallium(l) aryl xanthates thus produced are useful reagents for the metathetical synthesis of other metal derivatives. With 2-alkyl substituents on the phenol, the potassium salts can be obtained which are used directly to synthesize other metal derivatives. The properties of the aryl xanthates are similar to those of other l,l-dithiolates. The complexes are somewhat more susceptible to thermal and atmospheric decomposition than the analogous alkyl derivatives.

Synthesis and Properties of β-Diketone Complexes of Oxovanadium(V)

Abstract The synthesis and properties of some oxovanadium(V) chloride complexes of β-diketones are reported including the preparation of the air-stable dibenzoylmethane derivative. The materials appear to be mild chlorinating reagents, decomposing in the process to stable oxovanadium(IV) products.