Patent GB-599155-A (GB)
Title: Process for the production of thioamides
IPC: C07D209/48
Filed: 1945-07-04
Abstract: Acylamidoalkyl or acylimidoalkyl carboxylic thioamides of the general formula <FORM:0599155/IV/1> where n is an integer, R represents hydrogen and X represents the residue of an aromatic, araliphatic or heterocyclic carboxylic or sulphonic acid or X and R together represent the residue of an organic dicarboxylic acid, are prepared by treating an acylamidoalkyl or acylimidoalkyl cyanide of the general formula X.NR.(CnH2n).CN, where X, n and R have the above significance, with hydrogen sulphide in the presence of ammonia, ammonium sulphide or an organic base.  The group X may be a benzoyl or benzene sulphonyl group, a substituted benzoyl or benzene sulphonyl group (in which the substituent group is an alkyl, halogen, hydroxyl or alkoxy group, an amino group or a group readily convertible into an amino group such as an acylamino, dialkylamino, nitro, nitroso, azo or hydrazo group), or a phenylacetyl, phenylethane sulphonyl, picolinyl, nicotinyl or isonicotinyl group. The acylamido alkyl cyanides may carry the acylamido group on any carbon atom in the chain, e.g. a - or b -acylamidopropionitrile, a -, b - or g -acylamido-butyronitrile, e -acylamidocapronitrile or an acylamidoundecanonitrile.  Suitable organic bases are mono-, di- or triethanolamine or a mixture thereof such as is obtained by the interaction of ethylene chlorohydrin and ammonia, the homologous compounds obtained by the interaction of ammonia with propylene, butylene and other olefine chloro- and bromohydrins or mixtures thereof, organic amines, e.g. ethylamine, n-butylamine and diethylamine and alkali metal alkoxides, e.g. sodium and potassium methoxides, ethoxides, isopropoxides or butoxides.  The ammonia or organic base may be dissolved in a suitable solvent such as a lower alkanol.  In examples: (1), (2), (4), (6) and (8) benzamido-thioacetamide, a -(benzamido) - thiopropionamide, a  - (p - acetamido - benzenesulphonamido) - thiopropionamide, g  - phthalimido-thio-n-butyramide and 11-benzamido thioundecanoamide are prepared by adding benzamido-acetonitrile, a -(benzamido)-propionitrile, a -(p-acetamido-benzenesulphon-amido)-propionitrile, g -phthalimido-n-butyronitrile or 11-benzamido-undecanonitrile, respectively, to a solution of ammonium sulphide in methyl alcohol; (3) b -(benzamido)-thiopropionamide is prepared by passing hydrogen sulphide into a solution of b -(benzamido)-propionitrile in methyl alcohol saturated with ammonia; (5) g -(p-acetamido-benzenesulphonamido)-thio-n-butyramide is prepared by adding g -(p-acetamidobenzenesulphonamido)-n-butyronitrile to an ethanolamine solution of hydrogen sulphide; (7) e -benzamido thiocaproamide is prepared either by saturating a solution of e -benzamido capronitrile in methyl alcohol with hydrogen sulphide and ammonia and then heating under pressure, or by passing hydrogen sulphide into a solution of e -benzamido capronitrile in methyl alcohol and sodium or methyl alcohol and triethanolamine and heating in a closed vessel.  Acylamidoalkylcyanides of the general formula XNR(CnH2n)CN, where n is an integer, R represents hydrogen and X represents the residue of an aromatic, aliphatic or heterocyclic carboxylic or sulphonic acid, are obtained by reacting the corresponding aminoalkylcyanides with the required aromatic, araliphatic or heterocyclic carboxylic acid halide or sulphonyl halide, e.g. benzene carboxylic acid halides or sulphonyl halides or benzene carboxylic acid halides or sulphonyl halides substituted with any of the substituents given above.  The examples describe the preparation of benzamido acetonitrile, a  - (benzamido) - propionitrile, b  - (benzamido)-propionitrile, e -benzamido-capronitrile, 11 - benzamido undecanonitrile, a  - (p - acetamido - benzenesulphonamido) - propionitrile and g  - (p - acetamidobenzenesulphonamido) - n - butyronitrile.  g -Phthalimido butyronitrile is prepared by reacting potassium phthalimide and g -bromo-n-butyronitrile.