GB673633A - Improvements in or relating to the production of substituted diamines and ª‡-pyridyl-ª‡-thenylamine intermediates therefor - Google Patents

Abstract

Diamines of the general formula <FORM:0673633/IV (b)/1> (wherein R1 and R2 each represent hydrogen or an alkyl group of 1-4 carbon atoms, or R2 may also represent chlorine, bromine or iodine, A represents an alkylene group of 2-11 carbon atoms, and R3 and R4 represent alkyl or aralkyl groups or may be joined to form a ring, and together contain a total of not more than 11 carbon atoms) are manufactured by treating at reaction temperatures, in the presence of a solvent which is or contains an acid-binding agent, an a -pyridyl-a 1-thenylamine with an o -R3,R4-aminoalkyl halide. Preferably the halide is a chloride and the reaction is carried out in an inert hydrocarbon solvent (e.g. benzene, toluene, xylene or petroleum ether) in the presence of an alkali metal (e.g. sodium) amide or hydride. The products are useful as chemical intermediates, and in some cases themselves possess physiological activity, e.g. some have antihistaminic and antispasmodic and some local anaesthetic properties. They may be converted into salts (e.g. hydrohalides, sulphates, phosphates, oxalates, succinates, fumarates, maleates, tartrates, gluconates, citrates or picrates) and quaternary ammonium compounds. Examples and a list illustrate the following meanings of the various symbols: R1=hydrogen and g -methyl, R2=hydrogen, b 1-methyl and a 11-bromo, A = -(CH2)2-, -(CH2)3-, -(CH2)11- and -CH2-C(CH3)2-CH2-, R3=methyl, ethyl or n-butyl, R4= as R3, or benzyl, or R3+R4+N = piperidino or morpholino. Specification 606,181 is referred to. a - Pyridyl - a 1 - thenylamines of the general formula <FORM:0673633/IV (b)/2> are manufactured by reacting an appropriate a -aminopyridine with an appropriate a -halomethylthiophene, or with an appropriate thiophene-a -aldehyde in the presence of a reducing agent (especially formic acid), or by reacting an appropriate a -halopyridine with an appropriate a -thenylamine. Examples describe the preparation of a -pyridyl-a 1-thenylamine and N - (a - pyridyl) - N - (a 11 - bromo - a 1 - thenyl) amine. Thiophene-a -aldehydes of the general formula <FORM:0673633/IV (b)/3> are obtainable by reacting a thiophene compound (e.g. a -bromothiophene) with an N-substituted formanilide (e.g. N-methyl-, N-ethyl- or N-phenyl-formanilide) in the presence of phosphorus oxychloride. The Specification as open to inspection under Sect. 91, comprises also the manufacture of compounds of the general formula above in which A may be a hydrocarbon radical other than alkylene, and R3 and R4 may be hydrogen, and the use of the processes of Specification 672,872 and of the additional processes described in that Specification (as open to inspection under Sect. 91). Additional examples are given. This subject-matter does not appear in the Specification as accepted.