Process for preparation of 6-aryl-4H-s-triazolo-[3,4-c]-thieno-[2,3-e]-1,4-diazepines

Claim 1

A process for the preparation of a 6-aryl-4 H-s-triazolo-[3,4-c]-thieno-[2,3-e]-1,4-diazepine of the formula ##STR32## wherein R 1 is hydrogen, halogen or alkyl of 1 to 2 carbon atoms; R 2 is hydrogen, chlorine, bromine, straight or branched alkyl of 1 to 3 carbon atoms, ω-hydroxyalkyl of 1 to 3 carbon atoms, cycloalkyl of 3 to 6 carbon atoms, tetrahydrofuranyl, tetrahydropyranyl, N-methyl-piperidyl or thienyl; and R 3 is hydrogen, fluorine, chlorine or bromine; which comprises the steps of (a) reducing a compound of the formula ##STR33## wherein R 1 and R 3 have the meanings defined above, and X is halogen, amino or carboxylic acyloxy, with sodium borohydride in dimethylformamide or dimethylacetamide at temperatures between 0° and +10° C. to form a corresponding carbinol of the formula ##STR34## wherein R 1 , R 3 and X have the meanings defined above; (b) treating the carbinol, optionally after conversion of the amino group into a halogen atom or after splitting off the acyl group, with a cyclization agent to form a carbonyl compound of the formula ##STR35## wherein R 1 and R 3 have the meanings defined above; (c) converting the carbonyl group into the mercapto, a lower alkoxy or an alkylmercapto group or into a halogen atom by conventional methods to form a compound of the formula ##STR36## wherein R 1 and R 3 have the meanings defined above, and X is Sh--, lower alkoxy, alkylmercapto or halogen; (d) reacting the compound thus obtained with a compound of the formula R.sub.2 --CO--NH--NH.sub.2 wherein R 2 has the meanings previously defined except chlorine and bromine; (e) optionally chlorinating or brominating a compound of the formula ##STR37## thus obtained, wherein R 1 and R 3 have the meanings defined above, with a chlorinating or brominating agent; (f) cleaving the oxazepine ring of the compound at the oxygen atom by treating it with a strong hydrohalic acid; (g) extracting the resulting hydrohalide of a compound of the formula ##STR38## wherein R 1 through R 3 have the meanings defined above and Hal 1 is halogen, with a water-immiscible solvent; (h) admixing the residue with a phosphorus halide or sulfur halide; (i) reacting the resulting dihalo compound of the formula ##STR39## wherein R 1 through R 3 have the meanings defined above, and Hal 1 and Hal 2 are halogen, with ammonia or an ammonia-releasing substance to form a compound of the formula ##STR40## wherein R 1 through R 3 have the meanings defined above; and (j) dehydrogenating the resulting compound with a halogen or a compound of the higher oxidation stage of chromium or manganese.