Patent GB-721081-A (GB)
Title: New chemical compounds useful as insect repellents
IPC: C07C255/45
Filed: 1952-12-22
Abstract: The invention comprises cyclohexyl-1-cyano-1 - (N - acyl - N - alkyl) - amines of the general formula <FORM:0721081/IV (b)/1> wherein Acyl represents an aliphatic, araliphatic or aromatic acyl radical.  Such compounds are obtained by reacting a cyclohexyl-1-cyano-1-(N-alkyl)-amine with a reactive functional derivative of an aliphatic, araliphatic or aromatic carboxylic acid. Alternative methods are the reaction of salts of aliphatic, araliphatic or aromatic acids with carbamic acid derivatives of cyclohexyl-1-cyano-1-N-alkylamines with the elimination of carbon dioxide and metal halide (when a carbamyl halide is used), or an arylated cyclohexyl - 1 - cyano - 1 - amine may be alkylated at the nitrogen atom of the amide group.  In an example (1) cyclohexyl-1-cyano-1-(N-butyroyl-N-methyl)-amine is prepared by reacting cyclohexyl - 1 - cyano - 1 - N - methyl - amine with butyric acid chloride.  Crotonic acid chloride, benzoyl chloride and acetyl chloride may also be used, and the N-ethyl derivatives may also be prepared.  Similarly prepared are cyclohexyl-1-cyano-1-(N-methyl-N - propionyl) - amine, cyclohexyl - 1 - cyano - 1 - (N - methyl - N - crotonoyl) - amine, cyclo - hexyl - 1 - cyano - 1 - (N - methyl - N - n - valeroyl) - amine, cyclohexyl - 1 - cyano - 1 - (N - methyl - N - benzoyl) - amine, cyclohexyl - 1 - cyano - 1 - (N - ethyl - N - o - chlorobenzoyl) - amine, and cyclohexyl - 1 - cyano - 1 - (N - methyl - N - p - chlorphenacetyl) - amine.  The products are useful as insect repellants (see Group VI).  Specification 512,691 is referred to.ALSO:An insect repellent composition comprises at least one compound of the general formula <FORM:0721081/VI/1> wherein "Acyl" represent an aliphatic, aromatic or araliphatic acyl radical, and a carrier.  Compositions of the above compounds or the compounds themselves may be applied to the human skin and also to linen, clothing, and other objects e.g. curtains and walls.  The compositions may be in the form of solutions, powders, creams, pastes, emulsions, sprays, or aerosols, or as vapours e.g. from fumigating spirals or candles.  The compositions may also contain other insect repellents, for example phthalic acid dialkyl esters, indalon, 2- ethyl hexyl diol-1, 2, crotonic acid-N-ethyl-o-toluidide, ochlorobenzoic acid diethyl amide, 3, 4-dimethyl benzoic acid morpholide, o- and p-chloro-benzyl-acetoacetic acid diethylamide; or other additions such as sun lotions e.g. umbelliferon; or pigments, perfumes, conserving agents or disinfectants.  Exmples describe (5) a powder suitable for cosmetic purposes comprising cyclohexyl-1-cyano-1-(N-butyroyl-N-methyl)-amine and talcum; (6) an emulsion obtained by mixing cyclohexyl-1-cyano-1-(N-ethyl-N-acetyl)-amine with a sulphated high molecular weight fatty alcohol and stirring the mixture into water; (7) a cosmetic lotion comprising cyclohexyl-1-cyano-1-(N-methyl-N-butyroyl) amine and castor oil dissolved in water; (8) a solution of cyclohexyl-1-cyano-1-(N-methyl-N-butyroyl) amine, chlorobenzyl-aceto-acetic acid edliethyl amide and benzoic acid diethylamide in isopropanol.  The benzoic acid diethylamide may be replaced by dimethyl phthalate, olive oil, paraffin oil or crotonic acid -N-ethyl-o-toluidide; (9) an ointment comprising cyclohexyl-1-cyano-1-(N-butyroyl-N-methyl) amine in a mixture of liquid paraffin, stearic acid, wool fat, wax, triethanolamine, glycerol, water and a little ammonia; (9) the impregnation of filter paper (previously impregnated with potassium nitrate) with an acetone solution of cyclohexyl-1-cyano-1-(N-methyl-N-butyroyl) amine, to give a fumigating paper.  Other radicals specified for "Acyl" are acetyl, crotonoyl, benzoyl, o-chlorobenzoyl, valeroyl, and pchloro-phenacetyl.  The preparation of compounds of the above general formula is described (see Group IV (b)). Specification 512,691 is referred to.