Open-ended, singly metalated dithiolene complexes with 1,2,4,5-tetrakis(diphenylphosphino)benzene (tpbz) are prepared either by ligand transfer to [Cl 2 M(tpbz)] from (R 2 C 2 S 2 )SnR′ 2 (R = CN, R′ = Me; R = Me, R′ = n Bu) or by a direct reaction between tpbz and [M(S 2 C 2 R 2 ) 2 ] (M = Ni, Pd, Pt; R = Ph, p -anisyl) in a 1:1 ratio. The formation of dimetallic [(R 2 C 2 S 2 )M(tpbz)M(S 2 C 2 R 2 )] attends these syntheses in modest amounts, but the open-ended compounds are readily separated by silica chromatography. As affirmed by X-ray crystallographic characterization of numerous members of the set, the [(R 2 C 2 S 2 )M(tpbz)] compounds show dithiolene ligands in their fully reduced ene-1,2-dithiolate form conjoined with divalent Group 10 ions. Minor amounts of octahedral [(Ph 2 C 2 S 2 ) 2 Pt IV (tpbz)], a presumed intermediate, are isolated from the preparation of [(Ph 2 C 2 S 2 )Pt II (tpbz)]. Heterodimetallic [(Ph 2 C 2 S 2 )Pt(tpbz)Ni(S 2 C 2 Me 2 )] is prepared from [(Ph 2 C 2 S 2 )Pt II (tpbz)]; its cyclic voltammogram, upon anodic scanning, shows two pairs of closely spaced, but resolved, 1e – oxidations corresponding first to [R 2 C 2 S 2 2 – ] – 1e – → [R 2 C 2 S • S – ] and then to [R 2 C 2 S • S – ] – 1e – → [R 2 (C=S) 2 ]. The open diphosphine of [(R 2 C 2 S 2 )M(tpbz)] can be oxidized to afford open-ended [(R 2 C 2 S 2 )M(tpbzE 2 )] (E = O, S). Synthesis of the octahedral [(dppbO 2 ) 3 Ni][I 3 ] 2 [dppbO 2 = 1,2-bis(diphenylphosphoryl)benzene] ...

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Metallodithiolene complexes of the type [(R2C2S2)M(η2-tpbz)] [R = CN, Ph, or p-anisyl; M = Ni2+, Pd2+, or Pt2+; tpbz = 1,2,4,5-tetrakis(diphenylphosphino)benzene] chelate transition metals ions to form trimetallic arrays [[(R2C2S2)M(tpbz)]2M′] n+, where M′ is square planar Pt2+, tetrahedral Cu+, Ag+, or Au+, or octahedral {ReBr(CO)}/{Re(CO)2}+. Forcing conditions (190 °C reflux in decalin, 72 h) are demanded for the Re+ compounds. With third-row metals at the nexus, the compounds are stable to air. Twelve members of the set have been characterized by X-ray diffraction and reveal dithiolene centroid–centroid distances ranging from 22.4 to 24.0 Å. Folding around each tpbz intrachelate P···P axis such that the MP2/M′P2 planes meet the tpbz P2C6P2 mean plane at non-zero values gives rise to core topologies that appear “S-like” or herringbone-like for M′ = Pt2+ or {ReBr(CO)}/{Re(CO)2}+. Calculations reveal that departure from idealized D 2h /D 2d /C 2v symmetries is induced by steric crowding between Ph groups and that dynamic, fluxional behavior is pertinent to the solution phase because multiple, lower-symmetry minima of comparable energy exist. Spectroscopically, the formation of the trimetallic arrays is marked by a shift of the open end 31P nuclear magnetic resonance signal from approximately −14.5 ppm to approximately +41, approximately +20.5, and approximately +28.5 ppm for M′ = Pt2+, Au+, and {ReBr(CO)}/{Re(CO)2}+, respectively. Electrochemically, dithiolene-based oxidations are observed for the R = Ph and M′ = Pt2+ or Au+ compounds but at potentials that are anodically shifted relative to charge-neutral [[(R2C2S2)M]2(μ-tpbz)]. The compounds reported clarify the possibilities for the synthesis of assemblies in which weakly coupled spins may be created in their modular (R2C2S2)M and M′ parts.

The title compound, [Ni(C22H26S2)2], 1, is a square-planar D 2h -symmetric compound that occurs on a general position in non-centrosymmetric tetragonal P41212 (No. 92) with ¼ eq of n-pentane (C5H12) as co-crystallite. Intraligand bond lengths show the dithiolene ligands to be in their half-oxidized radical monoanionic form. Intermolecular t Bu-C—H...arenecentroid and t Bu-C—H...NiS2C2 centroid close contacts guide the packing arrangement for 1.