Anisoylthiocarbimide and its Derivatives.

Experiments on the same lines as those with benzoylthiourethane, using the corresponding anisoyl compound, led to similar results; the anisoylthiocarbimide, CHO CH4 CO NCS, required was prepared as usual by heating the acid chloride, dissolved in benzene, with lead thiocyanate; the clear, pale yellowish-brown, practically odourless solution thus obtained was easily desulphurised by lead and silver salts. Advantage was taken of the opportunity to prepare a number of other derivatives, an account of which is given below.

Ethylic imidoanisoylthiocarbonate (anisoylthiourethane),

CH,O•CH_•CO•N:C(SH)•OC,H.

-Obtained by gently warming the thiocarbimide in benzene with excess of absolute alcohol; the velvety mass of yellow crystals left on evaporating the solvents, crystallised from light petroleum in rosettes of snow-white, microscopic needles melting at 70-71°. The yield was 94 per cent. of that theoretically obtainable from the weight of anisoyl chloride employed.

0.2059 gave 0.2 BaSO4. S = 13.35.

CHINOS requires S 13.41 per cent.

13

=

The substance is slightly soluble in boiling water, and is deposited, on cooling, in oily droplets which soon crystallise; it dissolves easily in alcohol, benzene, chloroform, carbon bisulphide, and aqueous potash ; the last named solution is moderately easily desulphurised by boiling with alkaline lead tartrate. Ammoniacal nitrate of silver gives a curdy, white precipitate, soluble on heating; the solution gradually darkens when boiled.

The potassium compound was obtained by mixing alcoholic potash (1 mol.) with the concentrated alcoholic solution of the thiourethane (1 mol.), and washing the solid product with ether; it formed white crystals, freely soluble in water, moderately in alcohol, sparingly in ether, and melting, with effervescence, at about 222° (uncorr.).

It was dissolved in spirit, boiled with ethylic iodide, and saturated with ammonia, in the same way as the corresponding benzoyl compound, and with like results; the solid product, after being broken up, washed with water, and recrystallised first from chloroform and then from light petroleum, formed vitreous, pointed prisms, softening slightly at 67° and melting at 69–70°.

0.207 gave 22.9 c.c. moist nitrogen at 17° and 763 mm. N=12.96. CH2O CH, CO⚫N: C(NH2) OC2H, requires N = 12.64 per cent.

5

Ethyl-in-anisoylurea is very sparingly soluble in boiling water,

sparingly in hot light petroleum, but freely in alcohol, chloroform, benzene, and hot carbon bisulphide.

Working on the above lines, several attempts were made to obtain a phenylic analogue, NPh: C(OEt) NH,, but without success.

Anisoylthiourea, CSN2H, CO CHOCH.-Separated at once, on mixing alcoholic ammonia with the benzene solution of the thiocarbimide; yield, 83 per cent. of the theoretical. It was deposited from spirit in mixed rhombs and octahedra, vitreous and brilliant, melting at 216-217° (corr.).

0.2014 gave 0.2263 BaSO4 S = 15.45.

CH10NOS requires S= 15.25 per cent.

The substance is practically insoluble in boiling water, rather sparingly soluble in boiling alcohol, very sparingly in cold, freely in chloroform and hot benzene, and moderately in warm carbon bisulphide; the benzene solution is precipitated on adding light petroleum. It is also soluble in warm, dilute, caustic potash; this solution is readily desulphurised by heating with lead tartrate, and gives, with hydrochloric acid, a precipitate which does not dissolve in excess of acid. Anisoylthiohydantoin (n-Anisoylthiourantoin) (Trans., 1897,71,638).— Anisoylthiourea was fused with monochloracetic acid; the product, after being well washed with spirit, formed a pale-yellow powder, insoluble in water or the usual organic solvents, but easily soluble in dilute potash to a clear, bright red solution, which is precipitated by hydrochloric acid, the precipitate being soluble in excess of the acid. Heated in a narrow tube, it sinters and darkens at about 222°, and is blackened and decomposed at 230° (uncorr.). The solution in alkali is very slightly desulphurised by boiling with lead tartrate, owing, probably, to the presence of a trace of unchanged thiourea; when boiled alone, the solution gives the iron reaction for thioglycollic acid. It is almost insoluble in alcohol; the solution gives, with ammoniacal silver nitrate, a yellowish, amorphous precipitate, which scarcely darkens on boiling. The product thus appears to be, substantially at S-CH2 NH.CO

least, anisoylthiourantoin, CH2O C2H1· CO •N: C<

0.204 gave 0.1952 BaSO. S=13.15.

C11H10N2SO3 requires S = 12.81 per cent.

ab-Anisoylphenylthiocarbamide, CH2O CH1 CO·NH·CS NHCH5. -Heat was evolved on mixing the constituents, and yellowish crystals presently separated, the yield amounting to 90 per cent. of the theoretical. By recrystallisation from spirit, brilliant, vitreous prisms were obtained, melting at 1255–126° (corr.).

0.2014 gave 0.1677 BaSO. S=11·45.

C15H14N2O2S requires S = 11.20 per cent.

The substance is insoluble in water, easily soluble in boiling alcohol, rather sparingly in cold, moderately in carbon bisulphide, freely in acetone, benzene, and chloroform: the last two solutions are precipitated on adding light petroleum. It is easily desulphurised by heating with lead tartrate, and, with ammoniacal silver nitrate, yields a white precipitate which is blackened on warming. The solid dissolves in warm dilute caustic alkali, separating out again unchanged when the solution cools.

ab-Anisoylorthotolylthiocarbamide.-Over 92 per cent. of the theoretical yield was obtained; the product, when recrystallised from alcohol, formed almost colourless prisms, melting at 126.5° (corr.).

Found, S=10.89. C16H16N2SO2 requires S = 10.68 per cent.

It is insoluble in water, easily soluble in hot alcohol, rather sparingly in cold, and is desulphurised by silver and lead salts, like the phenylic homologue.

ab-Anisoylparatolylthiocarbamide.-This compound separated at once when the paratoluidine was added; the yield amounted to 95 per cent. of the theoretical. When recrystallised from alcohol, it formed colourless prisms, melting at 127-128° (corr.).

Found, S=10.9; Calculated, 10.68 per cent.

Its properties resemble those of the ortho-derivative. ab-Anisoylmethylthiocarbamide.-Prepared from 33 per cent. aqueous methylamine; the yield was only 58 per cent. of the theoretical. The recrystallised substance occurred in colourless prisms, melting at 143-144° (corr.), and gave 14-42 per cent. of S, against 14.30 required. It is slightly soluble in water, otherwise its properties resemble those of the preceding compound.

ab-Anisoylethylthiocarbamide.-Prepared like the methylic homologue; the yield in this case was nearly quantitative. After recrystallisation, it formed thick prisms, melting, without decomposition, at 126.5-127.5° (corr.). A sulphur determination gave 13.68 per cent., against 13.46 required for C12H14N,SO2. Its properties are similar to those of the methyl compound, except that it is rather more soluble in alcohol. It dissolves in warm, dilute alkali; with hydrochloric acid, this solution gives a white precipitate, soluble in excess of the acid.

ab-Anisoylethylurea.-Obtained by desulphurising the preceding compound with silver nitrate; it formed lozenge-shaped, vitreous crystals, softening slightly at 145° and melting at 146-147° (corr.), that is, 77° above the -isomeride.

0-2009 gave 0.4402 CO, and 0·121 H2O. C-59-75; H=6·69. 0.2074 23-4 c.c. moist nitrogen at 19° and 768 mm. N=13·10. C11H14N2O3 requires C=59.42; H=6·32; N=12.65 per cent.

It is sparingly soluble in boiling water or cold alcohol, moderately in boiling alcohol, easily in warm, dilute caustic potash.

ab-Anisoylbenzylthiocarbamide. From the thiocarbimide and benzylamine; yield, 91 per cent. of the theoretical. When recrystallised from alcohol, in which it is moderately soluble at the boiling point but very sparingly in the cold, it formed colourless prisms, melting at 127-128° (corr.).

Found, S=10.91. C16H16N2SO2 requires S-10.68 per cent.

Its properties are similar to those of the ethylic compound. n-Anisoyl-v-phenylbenzylthiourea,

CH,O-CH-CO-N:C(SH)•N(C,H,) CH,CH.

-From benzylaniline; the yield was nearly quantitative. After three recrystallisations (from alcohol), the compound, when seen in mass, still retained a faint yellow colour; it occurred in brilliant, rhombic plates, sintering at 141° and melting at 142-143° (corr.).

Found, S=8.81. C22H20N2O2S requires S=8.52 per cent.

It is insoluble in water, only moderately soluble in boiling alcohol, sparingly in cold, or in light petroleum, easily in benzene. The alcoholic solution is not desulphurised by boiling with alkaline lead tartrate; ammoniacal nitrate of silver in excess gives a white precipitate which darkens only very faintly on heating. The presence of sulphur is easily recognised, however, by the evolution of hydrogen sulphide when the solid is heated in a dry tube.

I desire to express my thanks to Mr. R. E. Doran, for help afforded in the course of this work.

CHEMICAL DEPARTMENT,

QUEEN'S COLLEGE, Cork.

XXXVIII.-Action of Metallic Thiocyanates on Certain Substituted Carbamic and Oxamic Chlorides; and a New Method for the Production of Thiobiurets.

BY AUGUSTUS E. DIXON, M.D.

CONCERNING the action of lead and other metallic thiocyanates on halogenised organic compounds, a number of communications have recently been made from this laboratory (Trans., 1895, 67, 565,

1040; 1896, 69, 855, 1593; 1897, 71, 617); the present paper includes an account of results obtained with the chlorides of certain nitrogenous acids.

So far as data are yet available, the nature of the interaction between inorganic thiocyanates and halogenised organic compounds appears to depend mainly on the way in which the halogen is attached, although its occurrence and extent are further influenced by the presence or absence of solvent, the nature of the solvent, the temperature, the particular inorganic radicle employed, and the time occupied in withdrawing the halogen.

As regards the first point, every compound hitherto examined containing the group -CO.Cl united with an organic radicle, under suitable conditions exchanges its halogen for the thiocyanic residue, the product in each case functioning towards primary and secondary amines, alcohols, phenylhydrazine, and lead or silver solutions, not as a true thiocyanate, but as a thiocarbimide. Dicarboxylic acid chlorides yield analogous derivatives, for instance, C2H (CO-NCS), and carbonyl chloride itself, if heated with lead thiocyanate in presence of toluene, affords much thiocarbimidic product, whether CO(NCS), or not is still uncertain.

From ordinary thiocarbimides, these acidic compounds differ in being more or less easily decomposable by water, with formation of thiocyanic acid or carbonyl sulphide; moreover, some of them, although uniting readily with amines, are broken up on contact with ammonia into a corresponding amide and thiocyanic acid; it may be that the unstable forms are tautomeric.

The chlorine united with certain negative groups other than carbonyl is similarly exchangeable; thus thionyl chloride, sulphuryl chloride, chlorosulphonic acid, ethylsulphuric and phenylsulphonic chlorides all interact with metallic thiocyanates, affording thiocarbimidic products; but so far as they have yet been examined, these actions run less smoothly, and the complete withdrawal of the halogen appears to be a matter of difficulty. Phosphorus trichloride easily yields a substance having the general properties of an unstable acidic isothiocyanate, which is desulphurised by lead and silver salts, and combines spontaneously with aniline, to form a solid decomposable by water, with production of phenylthiourea. The study of this interesting action is still incomplete, but it seems as though the first product were phosphorus isothiocyanate, P(NCS), and the second, phosphorus triphenyltrithiourea, P(NH CS NHPh), the latter undergoing hydrolysis into phenylthiourea and an acid of phosphorus. Similar results have been obtained using phosphorus oxychloride.

It is well known that halogen in non-acidic combination can also be exchanged, but the products have no longer a thiocarbimidic