Isothiocyanate-methylamine

Isocyanates and isothiocyanates are reduced to methylamines on treatment with LiAlH4. Lithium aluminium hydride does not usually reduce azo compounds (indeed these are the products from LiAlH4 reduction of nitro compounds, 19-59), but these can be reduced to hydrazo compounds by catalytic hydrogenation or with... 

Soil. Soil metabolites include formaldehyde, hydrogen sulfide, methylamine, and methyl(methylaminomethyl)dithiocarbamic acid (Hartley and Kidd, 1987), the latter decomposing to methyl isothiocyanate (Ashton and Monaco, 1991 Hartley and Kidd, 1987 Cremlyn, 1991). The rate of decomposition is dependent upon the soil type, temperature, and humidity (Cremlyn, 1991). 

Methyl isothiocyanate has been prepared from methyl thiocyanate by rearrangement with heat1 and from A, A /-dimethyl-thiuramdisulfide by the action of iodine 2 or by heating with water or alcohol.3 The most useful method of preparation has been the reaction of methylamine with carbon disulfide to form methyl-... 

This is a general method for the preparation of alkyl thioureas. Ethylthiourea, m.p. 103-106°, has been prepared from ethyl isothiocyanate in the same manner. Di- and tri-alkyl thioureas may be prepared from alkyl isothiocyanates in a similar manner by substituting an equivalent amount of an amine solution in place of the ammonium hydroxide. Thus, sym -dimethylthiourea is prepared from methyl isothiocyanate and methylamine solution. A solution of dimethylamine and methyl isothiocyanate gives trimethylthiourea. 

The presence of a thiocyanate group can be very easily deduced from the IR spectrum, which contains a sharp, but weaker in intensity, IR band around 2150 cm-1 and an NMR carbon resonance between 112 and 115 ppm. In the case of psamaplin B (172), C-NMR additivity effects applied to the methylene carbon linked to the thiocyanate were used to distinguish between a thio- and isothiocyanate group [142]. Chemical proof can be provided by LAH reduction of the thiocyanate, which gives a thiol rather than a methylamine group as the reaction product of the reduction of the isothiocyanate [195]. 

Methyl thiourea Methylamine + carbon disulfide - CH3NHCSSNH4 Pb (N03)2 - methyl isothiocyanate + NH3 - methylthiourea... 

Isocyanates and isothiocyanates are reduced to methylamines on treatment with... 

The reaction of aryl isothiocyanates with pyrrole77 has been applied to the heterocyclic isothiocyanate ethyl 3-isothiocyanatopyridine-2-carboxylate and yields ethyl 3- [(pyrrol-2-yl)-thioearbonyl]amino pyridine-2-carboxylate (9), which can be used for cyclization reactions with hydrazine or methylamine to give the corresponding 3-substituted 2-(pyrroI-2-yl)-pyrido[3,2-[Pg.166]

The treatment of perfluoroalkyl phosphine oxides (291) with ammonia methylamine, or dlmethylamine, results in C-P bond cleavage with che formation of bis(perfluoroalkyl)phosphinic and thence (perfluoroalkyl)phosphonic amides the reactions of bis(perfluorobutyl)phosphinic fluoride are similar,except that with dlmethylamine when the main product is C FgP(0)F(NMe2). Lawesson s reagent converts aryl isocyanates into the corresponding isothiocyanates, but the thiazadiphosphetidine disulphides (292) are also important products of these reactions. The diazadiphosphetidines (293 R =Me) and (293 R =Ph) have been obtained during the aminolysis of the phosphonothioic... 

Benzylamines (80) were treated with methyl isothiocyanate to give the thioureas (81) which were -alkylated and exposed to methylamine to give dimethylbenzylguanidines Scheme 5.20.). Bethanidine (82) [89] was used to treat cardiac arrythmias, but its h)7potensive effect was too powerful. Meobentine (83) [90] possessed similar antiarrhythmic and antifibrillatory... 

In contrast, [2+2+2] cycloadducts 45 are obtained from from two equivalents of benzyli-dene methylamine and carbonyl isothiocyanates (R = COOEt, COSMe and CONPha) . 

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