Patent GB-730031-A (GB)
Title: Improvements in or relating to the preparation of organic nitrogen bases
IPC: C07D295/03
Filed: 1952-07-21
Abstract: Unsaturated amines and tetrahydro-1,3-oxazines are prepared by reacting in the presence of an acidic catalyst a hydrocarbon of at least 3 carbon atoms having a vinylidene group, formaldehyde and a basic compound of the formula Ro.Rx.NH, wherein Ro and Rx are each hydrogen, alkyl, aralkyl or cycloalkyl, or may be joined together to form the radical -CH2CH2CH2CH2-, -CH2CH2CH2 CH2CH2-, -CH2CH2OCH2CH2-, or CH2 CH2SCH2CH2-, which forms a heterocycle with the p  nitrogen atom.  The oxazines are usually formed in addition to unsaturated amines when the nitrogen compound is a primary amine or ammonia.  The formaldehyde and the nitrogen compound may be reacted in advance so that the unsaturated compound is reacted, for example, with methylene bisdimethylamine), hexamethylenetetramine, tertoctylazomethine &c. The acid catalyst may also first be added to the amine or ammonia to form a salt.  The reaction may be effected at temperatures of 50 DEG to 150 DEG  C. with or without a solvent, e.g. water, glacial acetic acid and inert organic solvents.  In the examples: (1) a -methylstyrene is reacted with N-tetramethylmethylenediamine in glacial acetic acid containing orthophosphoric acid to produce 2-phenyl-4-dimethylamino-1-butene.  This is hydrogenated to form N,N-dimethyl-3-phenyl-n-butylamine; (2) diethylamine, paraformaldehyde and a -methylstyrene are similarly reacted to give N,N-diethylamino-3-phenylbutene. Tetramethylmethylenediamine is reacted with (3) styrene, to give 1-phenyl-3-dimethylamino-1-propene; (4) a -pinene and (22) b -pinene to give compounds of the formula C10H15.CH2.N(CH3)2; (5) diisobutylene, to give the unsaturated amine C8H15.CH2.N(CH3)2; (6) camphene, in the presence of sulphonated styrene divinylbenzene copolymer, to give the amine C10H15.CH2N(CH3)2; (7) Monomethylamine hydrochloride, formaldehyde and a -methylstyrene yield the amine C6H5.C.CH3=CH.CH2NHCH3 and also the compound 3-methyl - 6 - methyl - 6 - phenyl - tetrahydro-1,3-oxazine; (8) using ethylamine hydrochloride, the 3-ethyl-6-methyl-6-phenyl-tetrahydro-1,3-oxazine was similarly prepared together with a small amount of phenylbutenylethylamine; (9) 2-phenyl-4-tert.-octylamino-1-butene is prepared from tert.-octylamine, paraformaldehyde and a -methylstyrene; (10) 2-phenyl - 4 - morpholino - 1 - butene is similarly prepared; (11) dipentene and tetramethyl methylene diamine yield the unsaturated amine C10H15.CH2.N(CH3)2; (12) propylene is reacted in an autoclave with tetramethylmethylenediamine to give butenyldimethylamine and another fraction which is apparently the amine from propylene dimer-heptenyldimethylamine; (13) a tertiary olefin is produced in situ by refluxing tert.-butyl alcohol in conc. sulphuric acid with tetramethyl methylene diamine in acetic acid to yield pentenyldimethylamine. A tertiary halide, e.g. chlorocumene in which the chlorine is in the alkyl group, may be used instead of the alcohol; (14) styrene is refluxed with paraformaldehyde and N-benzylmethylamine to yield N-cinnamyl-N-methylbenzylamine; (15) hexapropylene and tetramethylmethylene diamine yield nonadecenyldimethylamine; (16) ammonium chloride, formaldehyde and a -methylstyrene yield 6-methyl - 6 - phenyl - tetrahydro - 1,3 - oxazine; (17) cyclohexylamine, a -methylstyrene and a mixture of paraformaldehyde and aqueous formaldehyde yield 6-methyl-6-phenyl-3-cyclohexyl - tetrahydro - 1,3 - oxazine, and a little of 1 - cyclohexylamino - 3 - phenylbutene; (18) paraformaldehyde, N-benzylmethylamine and a -methylstyrene yield 1-N-methyl-N-benzylamino-3-phenylbutene; (19) phenyl dimethyl carbinol, prepared from cumene hydroperoxide and sodium sulphite, is used to prepare the unsaturated hydrocarbon in situ by heating with methylamine hydrochloride in aqueous formaldehyde. N-methylamino-3-phenylbutene and the tetrahydro-1,3-oxazine are formed; (20) b -pinene is reacted with ammonium chloride and formaldehyde to give an oil, tetramethyl bicyclo - (1,1,3) - hept - 2 - ene - 2 - ethylamine; (21) using methylamine instead of ammonium chloride in (20), the tetrahydro-oxazine is chiefly formed together with some unsaturated amine of the formula C10H15.CH2.NHCH3. Specifications 559,941 and 577,707 are referred to.