With ammonium thiocyanate

Compounds of type 184 were prepared similarly with R, = methyl and R2 = alkanoic esters (136, 229, 304) or carboxyethyl (4, 10, 13, 22, 220) (Table 11-27). Dichloroacetone reacts with ammonium thiocyanate, but... 

The cyclization of a-mercaptoketones with ammonium thiocyanate leads to the corresponding 2-mercaptothiazoles (144). For example, 2-mercapto-3-pentanone in ethereal solution with sulfuric acid gives 4-ethyl-5-methyl-2-mercaptothiazole (10), Ri = SH, R2 = Et, R3 = Me, when allowed to stand for 3 hr without heating with ammonium thiocyanate. 

Chloro-a,/3-unsaturated aldehydes condense with ammonium thiocyanate to give isothiazoles (76EGP122249). 2,3-Diphenylcyclopropenone reacts with iV-sulfinyl-cyclohexylamine in the presence of nickel tetracarbonyl to give the isothiazolin-3-one 1-oxide (197) (79SST(5)345). Cholesteryl acetate reacts with trithiazyl trichloride in pyridine to give the isothiazolo steroid (198) (77JCS(P1)916). 

The 6-methyl derivative (98, R = Me) was an important intermediate in the synthesis of analogs (e.g., 183) of folic acid. Korte has shown that 2-aminopyrido[3,2-guanidine carbonate with 3-aminopicolinic acid and that treatment of the same acid with ammonium thiocyanate or potassium cyanate yields the thioureido and ureido derivatives (100, X = S and X = 0). In contrast to the pyrido[2,3-d]pyrimidine system bsoth of these compounds could be cyclized by heat and the latter (100, X = O) is a likely intermediate in the synthesis of the dione (98) by the fusion with urea. 

The 5-methyl-5-ethyloxazolidine-2,4-dione may be prepared by reacting methyl ethyl ketone with sodium cyanide and with ammonium thiocyanate followed by desulfurization. This intermediate may also be prepared by condensing a-hydroxy-a-methylbutyramide with ethyl chlorocarbonate or by condensing ethyl a-hydroxy-a-methylbutyrate with urea. Another method described (Traube and Aschar, Ber., 46, 2077-1913) consists in the condensation of ethyl a-hydroxy-a-methylbutyrate with guanidine followed by hydrolysis. 

Successive treatment of 2-(bromomethyl)benzoyl bromide with ammonium thiocyanate and a secondary amine gives the acylthioureas 2, which cyclize in the presence of sodium carbonate to the 3-(disubstituted amino)benzothiazepinones 3.47... 

Re(VII), Mo(VI) and V(V) cations are detected by first spraying the chromatogram with tin(II) chloride solution (10% in 6 N hydrochloric acid) and then with ammonium thiocyanate solution (S0% in water). This leads to the formation of orange, pink or yellow-colored complexes [2]. 

Alternatively, the reaction of 93c (R = n-Bu) with ammonium thiocyanate in refluxing acetic acid gave the ammonium salt of N-phosphonomethylthiohydantoin 99 in moderate isolated yield (2). 

Mixtures of thiocyanates with chlorates (or nitrates) are friction- and heat-sensitive, and explode on rubbing, heating to 400°C, or initiation by spark or flame [1]. A violent explosion occurred when a little chlorate was ground in a mortar contaminated with ammonium thiocyanate. A similar larger-scale explosion involving traces of barium thiocyanate is also described [2],... 

Soliman and Belal investigated argentimetric (67,68) and mercurimetric (69) methods. Hydralazine precipitates silver from ammoniacal silver nitrate solution. The silver is dissolved with hot nitric acid and titrated with ammonium thiocyanate solution. Alternatively, mercury is precipitated from alkaline potassium mercuric iodide solution. The precipitated mercury is dissolved by adding excess standard iodine solution. The excess iodine is back-titrated with sodium thiosulfate solution after acidifying with acetic acid. 

Kriplani et al. <2005HC0527> published that Schiff bases formed from 2-amino-benzothiazoles 228 easily undergo ring closure to fused triazine-thiones 229 when treated with ammonium thiocyanate in dioxane under heating. The products were obtained in medium to good yields (49-70%). 

A favourable endothermic reaction occurs when barium hydroxide is mixed with ammonium thiocyanate. If you removed the stopper in photograph (B), you would detect the characteristic odour of ammonia. 

Cyclohexylurea has been prepared by the reaction of cyclo-hexyl isocyanate with gaseous ammonia or ammonium hydroxide, by thermal decomposition of cyclohexyl allophanamide, by treating cyclohexylamine hydrochloride with an aqueous solution of potassium cyanate," by heating nitrosomethylurea with cyclohexylamine, and by heating an ethanolic solution of cyclohexylamine and 3,5-dimethyl-l-carbamylpyrazole. 2,6-DimethyIphenyIthiourea has been synthesized by allowing 2,6-dimethylaniline hydrochloride to react with ammonium thiocyanate. ... 

Potassium chromate may be used as an indicator producing a red colour with excess Ag ion. More widely applicable is the method of back titration. Excess AgNOj is added to the sample containing chloride or bromide ions. The excess AgNOj is then titrated with ammonium thiocyanate and ammonium ferrous sulphate is used as an indicator of excess SCN. ... 

The corresponding amides, 311, upon treatment with ammonium thiocyanate give 312, presumably through intermediate thiazolidone species (Equation 113) <2001JHC507>. 

Reaction of Iron(III) Chloride with Ammonium Thiocyanate. 

The group VIB cyanides, thiocyanates and selenocyanates and their complexes with species such as thiourea have been described.1,45 For example, the tellurium dithiocyanate complex has been prepared45 by treatment of tellurium dichloride or tellurium dibromide with ammonium thiocyanate. It seems that little information exists on the preparation of tellurocyanates and there is a sparsity of data on polonium derivatives. Indeed, the only known cyanide of polonium is probably a salt of the quadrivalent element.1... 

Mercuric thiocyanate, which is formed as a white precipitate when mercuric nitrate and potassium thiocyanate solutions are mixed, is soluble in excess of either solution. When dried, this salt is inflammable, forming a voluminous ash known as Pharaoh s serpents. By the interaction of a mercuric salt with ammonium thiocyanate and thio-carbamide in acetic acid solution in the presence of an oxidising agent, or by the action of hydrogen sulphide on mercuric thiocyanate, the phototropic compound HS.Hg.CNS is obtained.6... 

Ammonium nitrate prepared from ammonia obtained by the dry distillation of coal should not be used as component of any explosive material because of the ammonium thiocyanate and pyridine present in it (the latter as nitrate). When the ammonia liquor from dry distillation of coal was the sole source af ammonia and ammonium nitrate, decomposition of mixtures containing ammonium nitrate with TNT (amatols), was brought about at the melting point TNT reacted with ammonium thiocyanate or with pyridine nitrate and evolved gaseous products. Minute traces of these impurities were sufficient to cause abundant gas evolution to develop during the fusion, pouring, and cooling of amatol. 

Thiocyanate. — On the basis of /-orbital hybridization Diamond [351] predicted the formation of stronger actinide complexes with thiocyanate ion than for the rare earths. Subls and Chopfin [352] have studied the ion exchange behaviour of many actinide and rare earth thiocyanate complexes and have shown that europium is eluted much sooner than americium from Dowex-1 with ammonium thiocyanate. The stability constants for the formation of MSCN2+ and M(SCN)2 complexes for Nd3+, Eus+, Pu3+, Am3+, Cm3+, and Cf34 have been measured [353] and are tabulated in Table 25. It is apparent from the table that the formation... 

A relatively large number of papers has described the preparation of oxo derivatives of 3,4-dihydro-2//-1,3-oxazine. The previously reported1 use of diketene as a cyclizing agent has found wider application. Gunar et al.1 described the reaction of diketene with ammonium thiocyanate. It passes through an intermediate acetoacetyl isothiocyanate to a 2-thiono derivative, which, on oxidation, yields 50 [Eq. (37)]. 

Treatment of the 9-formyl derivatives (241 R3 = H) with thionyl chloride gave 9-chloromethylene-4-oxo-6,7,8,9-tetrahydro-4//-pyrido [ 1,2-u] pyrimidines, which were then transformed with ammonium thiocyanate to the 9-thiocyanatomethylene derivatives.284... 

Rhodanine has been prepared by the reaction of chloroacetic acid with ammonium thiocyanate 2 by the action of ethyl chloro-acetate upon ammonium dithiocarbamate in the presence of alcohol and hydrogen chloride 3 by saturating a solution of thioglycolic acid and potassium thiocyanate in absolute alcohol with hydrogen chloride 4 by ring closure of thiocarbamylthio-... 

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