Dithio-oxamide

A rapid method of preparation of [Mn(NH20H)2Cl2] has been reported that is easily carried out and does not require the use of hydroxylamine. It involves treatment of manganese(ii) carbonate with hydroxylamine hydrochloride in boiling water. The complexes formed between Mn and tetramethyl- and tetraethyl-dithio-oxamide have been investigated by the Job method MnL3X2 (X = C10 or FeCl4 ) were observed. ... 

The complexes of tetramethyl- and tetraethyl-dithio-oxamide have been investigated by the Job method, and [FeLjX ] (X = CIO or FeClJ were identified. The i.r. spectrum of [Fe(TMSO) ] is very similar to that of the DMSO analogue. 1,4-Dithiane monosulphoxide forms the complexes [FeX lDTMSOlJ (X = Cl. Br, I. NO3. or NCS = 2, 3, or 6). ... 

Dithio-oxamide (LH4) and dimethyldithio-oxamide (LMH2) form complexes of types Ni4(LH2)5 and Nig(LM)9 which have anomalous magnetic moments 405 The complex of iViV-diethylphenylazothioformamide (143) [NiL2]2+, formed by reaction of nickel perchlorate with the ligand in acetone, is a member of a facile redox series... 

Dithio-oxamide (LH2) and its dimethyl and dicyclohexyl derivatives form polymeric [CuL]n probably with S2N2 co-ordinated copper.405 The copper complexes of l,10-phenanthroline-2-carbothiamide, CuLX2 (X = Cl, Br, or NCS), are six-co-ordinate with X-bridges. The N-phenyl-l,10-phenanthroline-2-carbothiamide complexes of copper are similar to those of Co111, in that only species containing the deprotonated ligand can be obtained, Cu(L - H)X (X = Cl, Br, or N03). 

Complexes of several S-donor ligands have also been reported. The reaction of dithio-oxamide and its tetramethyl and tetraethyl derivatives with zinc, cadmium, and mercury halides leads to complexes of stoicheiometry MLX2 (M = Zn, Cd, or Hg X = Cl, Br, or I).64,65 M—S bonding is involved i.r. spectra show that the zinc and mercury complexes are four-co-ordinate, while the cadmium complexes are octahedral with halogen bridges. The complexes [ML3][C104]2 have also been prepared and do not contain co-ordinated perchlorate. The complexes ZnL (H2L = dithio-oxamide, NiV-dimethyl- and IVA -dicyclohexyl-dithio-oxamide) have been isolated,66 and consist of linear chains containing four-co-ordinate zinc. 

Yields are diminished if the filiation is conducted prior to the addition of the metal, indicative of the thermal instability of these dithioamides. Furthermore, the yields are lower when Ni(II) salts are used in place of Ni powder, consistent with the oxidative character of the dithioamide. Nickel dithiolenes of the dithio-oxamides exhibit extraordinary extinction coefficients ( 80,000 dm3 mol em 1 at 1000 nm) (186, 187). 

Rubeanic acid (0-5%). Dissolve 0-5 g rubeanic acid [or dithio-oxamide] NH2, CS.CS.NH2 in 95 per cent ethanol and dilute the solvent to 100 ml. The solution decomposes rapidly and should be prepared freshly each time. 

Rubeanic acid (0 02%). Dissolve 20 mg rubeanic acid (dithio-oxamide), NH2.CS.CS.NH2, in 100 ml glacial acetic acid. The reagent should be prepared freshly. 

Copper(II) and nickel(II) react with dithio-oxamide to produce insoluble compounds of high molecular mass (Jensen, 1944), which contain long chains of the type ... 

The preparation of 1 1 complexes of arsenic, antimony, and bismuth trihalides with dithio-oxamides has been reported.647 I.r. spectra of the arsenic compounds point strongly to the probability of dimeric, octahedral structures, but with the two heavier Group V elements square-pyramidal structures have been suggested. Crystalline adducts 2MBr3,3dioxan, where... 

Among the organosulphur compounds proposed for the spectrophotometric determination of selenium, are Bismuthiol II (known as a reagent for Te) [41], 1,4-diphenylthiosemicarbazide [42], 2-mercaptoethanol [43], dithio-oxamide (rubeanic acid) [44], and DDTC [45]. Dithizone has been a basis for a sensitive method of determining Se (e = 7.4-10 ) [46]. The mechanism of the reaction between Se(fV) and dithizone is still the subject of contradictory opinions [47,48]. 

The base-catalysed reaction of nitriles with hydrogen sulphide is a well-known route to thioamides, and has been exemplified recently in multi-step syntheses of heterocyclic systems. " Cyclohexane-1,1-dithiol acted as a source of hydrogen sulphide in its reaction with cyanogen, thus yielding thio-oxamide or dithio-oxamide, depending on the amount of water in the reaction solvent. ... 

The Hantzsch thiazole synthesis from thioamides and a-halogeno-ketones has been applied to iVAr-(dimethyl)dithio-oxamide to give 2-(dimethylthio-carbamoyl)thiazoles, but in some cases it took another course. Thus, 1-alkylthiocarbamoyl-l-cyanoacetophenones (91) react with bromo-ketones with elimination of alkylamine, giving 2-methylidene-l,3-oxathioles (92). The thio-anilide of acetoacetic acid reacts with 2-bromo-l-tetralone to give the spiro-... 

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