Rhenium 1,1-dithiolato complexes

The only technetium complex has been reported (226) is [Tc(CO)4(R2dtc)]. There appear to be few reports of rhenium or technetium complexes with 1,1-dithiolato ligands. 

The methylation of Re[S2C2Ph2]3" gives a purple monomethyl derivative (20), Re[(CH3)(S2C2Ph2)3], which possesses all properties of a dithiolate. The existence of 19 confirms the ground state description of the neutral group VI metal trisdithienes (12, 13, 14) and shows that the complexes are electron deficient and two electrons short of the tris-dithiolato structure (15). With these conclusions and the results of the methylation experiment, we formulate the neutral trisdithiene of rhenium as a resonance-hybrid of the three limiting structures, 21, 22, 23 ... 

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