GB439722A - Manufacture of cyclic amines - Google Patents

Abstract

Cyclopolymethylene imines containing at least six carbon atoms in the ring are prepared from reactive esters of aminoalcohols of the formula HRNAOH, where A is a normal alkylene chain of at least six carbon atoms and R is hydrogen or alkyl, by heating solutions of the esters in an organic or aqueous organic solvent or in an aqueous solution of an organic hydrotropic salt, in the presence or absence of an alkaline reagent. The esters used are those in which the acid residue is easily exchangeable, e.g. the esters with hydrohalic or arylsulphonic acids. In the examples: (1) cyclopentadecamethylene imine is prepared by heating an ethereal solution of 1-bromo-15-aminopentadecane; (2) cyclooctamethylene imine is prepared by heating a benzene solution of 1-bromo-8-aminooctane; (3) as in example 1, except that petroleum ether is used as solvent; (4) cyclopentadecamethylene imine is prepared by heating 1 - bromo - 15 - aminopentadecane hydrobromide in butyl alcohol containing aqueous caustic soda; (5) as in example 1, except that dibutyl ether is used as solvent; (6) cyclopentadecamethylene imine is prepared by heating 1 - bromo - 15 - aminopentadecane hydrobromide dissolved in an aqueous solution of sodium benzoate and caustic soda; (7) cyclopentadecamethylene imine is prepared by heating 1 - bromo - 15 - aminopentadecane hydrobromide in ethyl or methyl alcohol containing aqueous caustic soda; (8) cyclohexadecamethylene imine is prepared as in example 4 from 1 - bromo - 16 - aminohexadecane hydrobromide. A sample has been furnished under Sect. 2 (5) of the picrate of N-methylcyclopentadecamethylene imine prepared as in example 4 from N-methyl - 1 - bromo - 15-aminopentadecane hydrochloride. Halogenamines.--1 - Bromo - 15 - aminopentadecane hydrobromide, used in some of the examples, is prepared by treating 1 : 15 - dibromopentadecane with potassium phthalimide, and saponifying the 1-bromo-15-phthalimidopentadecane obtained with hydrobromic and acetic acids. 1-Bromo-8-aminooctane and 1-bromo - 16 - aminohexadecane, required for examples 2 and 8, are prepared similarly from 1 : 8 - dibromoctane and 1 : 16-dibromohexadecane respectively. N-Methyl-1-bromo-15-aminopentadecane, used in making the sample, is prepared by treating p-toluenesulphonamide with 1 : 15-dibromopentadecane in butanol in the presence of sodium butylate, methylating the product with dimethyl sulphate, and saponifying with acetic and hydrobromic acids. The Specification as open to inspection under Sect. 91 defines A in the formula above as a substituted or unsubstituted hydrocarbon chain, which may be interrupted by other atoms such as oxygen or sulphur; R is defined as any hydrocarbon residue. It is stated also that the hydrogen atom attached to nitrogen in the formula may be replaced by a hydrocarbon residue. This subject-matter does not appear in the Specification as accepted.