GB758144A - Improvements in or relating to substituted tetrahydronaphthalenes and the preparation thereof - Google Patents

Abstract

The invention comprises substituted 1,2,3,4-tetrahydronaphthalenes of the general formula <FORM:0758144/IV(a)/1> wherein R and R1 represent hydrogen or an alkyl radical containing from 1 to 10 carbon atoms or together form a saturated heterocyclic ring with the nitrogen atom, and the acid addition and quaternary salts thereof, and the preparation thereof by reducing the corresponding amide with lithium aluminium hydride preferably in the presence of an ether under anhydrous conditions. The acid addition salts are formed by the addition of an acid, e.g. hydrochloric, hydrobromic, hydriodic, sulphuric, nitric, acetic, citric, lactic or tartaric acid, and the quaternary salts are formed by the addition of a quaternary salt-forming agent, e.g. an alkyl halide or sulphate such as methyl iodide, propyl chloride, allyl bromide, ethyl chloride or dimethyl sulphate. In the examples, 1 - aminomethyl -, 1 - methylaminomethyl -, 1 - dimethylaminomethyl -, 1 - piperidinomethyl -, and 1 - isopropylaminomethyl-1,2,3,4-tetrahydronaphthalene and their hydrochloride salts are prepared. A number of additional amide reactants and amine products are also referred to in which the group <FORM:0758144/IV(a)/2> in the general formula above represents the ethyl-, propyl-, butyl-, pentyl-, hexyl-, heptyl-, octyl-, diethyl-, dipropyl-, dibutyl-, dipentyl-, dihexyl-, diheptyl-, dioctyl-, methylethyl-, methyl-, ethylbutyl-, and butylhexyl-amino radical, and the pyrrolidino and morpholino radical. Starting materials: 1,2,3,4-Tetrahydronaphthoamides of the general formula <FORM:0758144/IV(a)/3> wherein R and R1 represent hydrogen or an alkyl radical containing from 1 to 10 carbon atoms or together form a saturated heterocyclic ring with the nitrogen atom, are prepared by reacting 1,2,3,4-tetrahydro-1-naphthoic acid with thionyl chloride to form 1,2,3,4-tetrahydro-1-naphthoyl chloride which is then reacted with the required amine. The preparation of 1,2,3,4-tetrahydro - 1 - naphthoamide, N - methyl - and N,N - dimethyl - 1,2,3,4 - tetrahydro - 1 - naphthoamide, and N - (1,2,3,4 - tetrahydro - 1-naphthoyl)-piperidine is detailed. A number of additional amides are referred to and are listed above.