Oxidative addition of the electron-rich tetra-methoxy-dibenzo-1,2,5,6-tetrathiocine [(MeO)2C6H2S2]2 to zero-valent group 10 transition metal complexes in the presence of diphenylphosphinoethane (dppe) affords the corresponding dithiolate complexes, [(DMOBD)M(dppe)] (DMOBD = dimethoxybenzenedithiolato, (MeO)2C6H2S2(2-); M = Ni, Pd, Pt) in high yield which were characterized by single crystal X-ray diffraction. Whereas the Pd and Pt complexes exhibit two quasi-reversible 1e(-) oxidation processes, the nickel species undergoes a quasi-reversible 1e(-) reduction.

The outcome of the oxidative addition reactions of bis(4',5'-dimethoxybenzo)-1,2,5,6-tetrathiocin to Pd2dba3 under microwave conditions is sensitive to the nature of the phosphine coreagent; the bidentate phosphines dppm, dppe, and dppf afford the mononuclear dithiolates (dmobdt)Pd(dppm) (4), (dmobdt)Pd(dppe) (2), and (dmobdt)Pd(dppf) (5), whereas more labile monodentate phosphines lead to aggregation; Ph3P afforded the dinuclear dithiolate (dmobdt)2Pd2(PPh3)2 (6), whereas (t)Bu3P generated the phosphine-free hexanuclear edge-capped octahedral complex Pd6(dmobdt)6 (7) [dmobdt = 4,5-dimethoxybenzenedithiolate, (MeO)2C6H2S2(2-)].

Functionalized benzenedithiolate complexes of Pt and Pd were prepared by oxidative addition of a library of 1,2,5,6-tetrathiocins to M₂(dba)₃. The oxidation potentials of crown-ether derivatives were increased upon binding Na⁺ ions.

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The synthesis and reactivity patterns of the strained dithiete ring are compared with their dimeric tetrathiocin counterparts and higher oligomers, highlighting: (i) their cycloaddition chemistry with organic dienophiles as a...