GB881894A - Tetrahydropyridine derivatives - Google Patents

Abstract

The invention comprises compounds of the general formula <FORM:0881894/IV (b)/1> and their acid addition salts wherein Ar and Ar1 are each a halophenyl alkoxyphenyl, containing up to eleven carbon atoms, dimethoxy phenyl, hydroxyphenyl, thienyl, trifluoromethylphenyl or monocyclic aromatic hydrocarbon radical containing less than eleven carbon atoms and wherein Alk is an C3-6 alkylene radical and the preparation thereof by (a) condensing an aroylalkyl halide of the general formula Ar-CO-Alk -Halogen with at least one equivalent of a compound of the general formula <FORM:0881894/IV (b)/2> or (b) reacting a compound of the general formula <FORM:0881894/IV (b)/3> with an aryl magnesium halide of the general formula Ar-Mg-halogen, decomposing the complex and recovering the product. g -Chlorobutyrophenone is prepared by condensing g -chlorobutyryl chloride with benezene in the presence of AlCl3, and similarly are prepared g - chloro - p - fluoro-, g ,p - dichloro -, g - chloro - p - bromo, g - chloro - p - methyl -, g - chloro - 2,4 - dimethyl -, g - chloro - 2,5 - dimethyl, - g - chloro - p - methoxy -, g - chloro - p - ethoxy -, g - chloro - p - propoxy -, g - chloro - p - butoxy -, and g - chloro - m,p - dimethoxy - butyrophenones. 2 - (g - Chlorobutyryl) thiophene is prepared from thiophene and g -chlorobutyryl chloride in benzene and in the presence of SnCl2. 2-(d -Chlorovaleryl) thiophene is similarly prepared. p-t-Butyl-a -methylstyrene is prepared by reacting methyl bromide and magnesium in ether with p-t-butylacetophenone. Similarly are prepared p-fluoro-, p-chloro-, p-bromo-, p-methyl-, p-ethyl-, and o,p-dimethyl-a -methylstyrene. 4-Phenyl-1,2,3,6-tetrahydropyridine is prepared by reacting a -methylstyrene with ammonium chloride and formaldehyde and hydrolysing the product. Similarly are prepared 4-(p-fluoro-phenyl)-, 4-(p-chlorophenyl), 4-(p-bromophenyl)-, 4-(p-methylphenyl)-, 4-(p-ethylphenyl)-, 4-(p-tertiary - butylphenyl) - and 4 - (o,p - dimethyl - phenyl - 1,2,3,6 - tetrahydropyridines as their hydrochlorides. g - Chloro-m-fluorobutyrophenone is prepared from g -chlorobutyronitrile and the Grignard reagent from m-fluorobromobenzene, as is g -m-dichlorobutyrophenone. g - (4 - Phenyl - 1,2,3,6 - tetrahydropyridine) - butyronitrile hydrochloride is prepared from g -chlorobutyronitrile and 4-phenyl-1,2,3,6- tetrahydropyridine. Phenol esterified with g -chlorobutyrylchloride gives phenyl-g -chlorobutyrate which treated with AlCl3 in nitrobenzene gives g -chloro-p-hydroxybutyrophenone.