Perthiocarbonate complexes

The structures of various (084) and ( 83) complexes have been determined (Tables I and III). The vibrational infrared, NMR, and electronic spectra of the Mo-trithio- and perthiocarbonate complexes have been compiled in Table XIII. The energy of the C=8 vibration of the coordinated ( 83) " ligands invariably is lower ( 980 cm ) than that of the C=8 vibration in the ( 84) complexes ( 1050 cm ) and can be used as a spectroscopic diagnostic criterion for the identification of the ligands with considerable confidence. An additional diagnostic indicator for the ( 83) and ( 84) ligands is the... 

Addition of CS2 to DMF solutions of [Ph4P] 2 [8=1 0(17 -84)2] and [Ph4P]2[(84)Mo284)(82)] results in the formation of perthiocarbonate derivative complexes (160) (Fig. 23 Table XIII). The illustrated pathways are based on C82 addition mechanisms involving the Mo-i7 -82 units. It should be noted that addition to the Mo=8 unit, followed by intramolecular 8 transfer, also is a possible pathway to (084) . Both cis and trans isomers of the [8=Mo( 17 -084)2] anion have been isolated (161). The [0=Mo (S4)2] complex is unreactive toward C82 unless activated by PhgP (73b). 

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