1.2- dithiosquarate

Homoleptic gold(III) complexes with other related dithiolate ligands, as dmit (317),1855-1864 dddt,1865,1866 l,3,5-trithiepin-6,7-dithiolate,1867 dithiosquarate (318),1868,1869 6,7-dihydro-6-methy-lene-5H-l,4-dithiepine-2,3-dithiolate,1870 3,4-thiophenedithiolate (319),1637 quinoxaline-3,3-dithiolate (320),1871 2,2-diacetylethylene-1,1-dithiolate,1872 or o-carborane-1,2-dithiolate have been... 

Two octanuclear copper complexes were reported. Of these, the arrangement of the copper atoms in a cube was suggested for [Cu—CgH4—m—CF3]g (76) and proved for the anion Cug(dts) " (dts = dithiosquarate) (266). 

The bis(dithiosquarate) complex K2[Ni(S2C402)2]-2H20 (299) has been obtained from aqueous solutions of K2S2C402-H20 and NiCl2-6H20. The complex is mononuclear, square planar and does not undergo reversible redox reactions.2151... 

The longest average M—S bond lengths for structures based on a particular element occur with the dithiosquarate ligand, S2C402 (Table IIC, Entry 52 ... 

There are 35 Au dithiolene units with formal metal oxidation states mostly as Au(III) and some as Au(IV) . The complexes are often considered alongside isoelectronic Pt bis(dithiolene) examples. Coordination geometries for all the Au structures are square planar as is the case for the Auidmit) 1 example shown in Fig. 8. Average Au—S bond distances range from 2.263-2.344 A (Fig. 5) and the longest Au—S bonds are observed with the dithiosquarate ligand (Table IIC, Entry 52). 

The photoluminescent behavior of a complex of the type Zn(diimine)(dtsq), where diimine = 2,2 -biquinoline, phen (44), or 4,7-diphenyl-2,9-dimethyl-phen (batho) and dtsq = dithiosquarate, have been reported by Gronlund et al (135). The phen and batho complexes display broad, featureless luminescence spectra in the solid state at room temperature. Upon cooling to 77 K, the emission spectrum of Zn(batho)(dtsq) resolves into three sharp peaks overlapping the broad emission feature these sharp peaks are assigned to a diimine localized ji-ji emission. The Zn(diimine)(dithiolate) solids degrade upon UV laser excitation, which has inhibited accurate lifetime measurements. 

The anion [Mn(SPh)4]2 was first prepared321 from the manganese compound of dithiosquarate dts (126) and [Mn(SPh)2dts]2 also was isolated. It probably represents another example of a tetrahedral [MnS4] species with a bidentate dithiol. 

The syntheses of the metal-benzenethiolate complexes are accomplished by a ligand substitution reaction between the appropriate O-ethyl dithiocarbonate complexes and potassium benzenethiolate, KSPh. In the original report on the syntheses of the [M(SPh)4]2 complexes,1 the bis(3,4-dimercapto-cyclobutane-1,2-dione) [dithiosquaric acid] metal complexes were used in the ligand substitution reactions. The rather involved synthesis of the dithiosquarate ligand,2 using expensive starting materials, prompted us to develop new synthetic procedures which utilize the readily available, inexpensive O-ethyl dithiocarbonate complexes.3... 

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