Patent GB-659353-A (GB)
Title: Improvements in or relating to chloromethylated higher aromatic hydrocarbons and quaternary ammonium compounds prepared therefrom
IPC: C07C17/32
Filed: 1949-05-04
Abstract: Aromatic hydrocarbons as defined below are chloromethylated by reacting them under anhydrous conditions with formaldehyde and hydrogen chloride (or with a chloromethyl ether) in the presence of a catalyst formed by mixing one mol. of zinc chloride with 1.5 to 8 mols. of an aliphatic carboxylic acids containing 1 to 3 carbon atoms; the acid may be replaced by its anhydride or a mixture of acids or anhydrides or of an acid and an anhydride. The hydrocarbons treated are alkyl-substituted benzenes containing: (1) one alkyl substituent of 8 to 18 carbon atoms with or without one or two alkyl substituents of 1 to 4 carbon atoms; or (2) two alkyl substituents of 5 to 12 carbon atoms with or without another alkyl substituent of 1 to 5 carbon atoms.  The acid used in the catalyst may be formic, acetic, chloracetic or propionic and is preferably present to the extent of 2 to 4 mols. per mol. of zinc chloride.  The molar ratio of catalyst to hydrocarbon is preferably 0.75-2.5 to 1, and that of formaldehyde to hydrocarbon 1.5-2.5 to 1.  The reaction is exothermic and is preferably carried out between 50 DEG  and 100 DEG  C., the temperature being controlled by the rate of addition of hydrogen chloride or chlormethyl ether.  Examples show the chloromethylation of dodecyltoluene, decylbenzene, octadecylbenzene and dioctyltoluene. Other suitable hydrocarbons are octylbenzene, octyltoluene, nonyltoluene, dodecylbenzene, dodecylxylene, tetradecyltoluene, hexadecyltoluene, diamylbenzene, dioctylbenzene, didodecylbenzene, triamylbenzene, diheptylbenzene, isopropyldodecylbenzene, sec.-butyldodecylbenzene and heptyloctylbenzene.  Quaternary salts are made by reacting the substituted benzyl chlorides, prepared as above, with tertiary amines at temperatures from room temperature to 100 DEG  C.  Alternatively, the substituted benzyl chloride may be reacted with a secondary amine and then with a quaternating agent. In the examples: (1) chloromethylated dodecyltoluene is reacted with trimethylamine, dimethyloctadecylamine, pyridine, N-methylpiperidine, dimethylethanolamine, methallyldimethylamine, N - methylmorpholine and methyl - diethanolamine; (2) chloromethylated dodecyltoluene is treated with dimethylamine and the resulting methyldodecylbenzyldimethylamine reacted with ethyl bromide and with methyldodecylbenzyl chloride; (3) chloromethylated decylbenzene is reacted with trimethylamine and with dimethylbenzylamine; (4) chloromethylated octadecylbenzene and dioctyltoluene are reacted with trimethylamine.  Other suitable amines are pyrrolidine, allyldimethylamine, ethyldimethylamine, diethanolamine and others containing alkyl groups of up to 24 carbon atoms.  The quaternary chlorides may be converted into other salts by metathesis, e.g. into bromides, iodides, fluorides, sulphates, phosphates, phenates and substituted phenates, e.g. dinitrophenates.  The preparation of methyldodecylbenzyltrimethylammonium pentachlorophenate is described. The quaternary salts are wetting agents and bactericides. Dodecyltoluene is prepared by treating toluene with a propylene tetramer and sulphuric acid below 10 DEG  C.  Octadecylbenzene is made by adding 1-octadecylene to a mixture of benzene and hydrofluoric acid below 10 DEG  C.  Mono- and di-octyl-toluenes are produced by treating toluenes with mixed octenes (boiling range 123-134 DEG  C.) in the presence of hydrogen fluoride below 10 DEG  C.