Process for preparing 2-hydrazino-1,3-diazacycloalk-2-ene hydrohalides

Abstract

This invention provides a process for preparing a 2-hydrazino-1,3-diazacycloalk-2-ene hydrohalide. The process comprises reacting a one molar proportion of either tautomeric isomer of a 2-nitroamino-1,3-diazacycloalk-2-ene represented by the following formulas: ##STR1## wherein R.sup.1 is hydrogen, C.sub.1 -C.sub.6 alkyl, C.sub.1 -C.sub.6 hydroxyalkyl, C.sub.1 -C.sub.6 alkoxyalkyl, phenyl, substituted phenyl, benzyl, or substituted benzyl, R.sup.2 and R.sup.3 are independently hydrogen, C.sub.1 -C.sub.6 alkyl, C.sub.1 -C.sub.6 alkoxy, C.sub.1 -C.sub.6 alkoxyalkyl, hydroxyl, aryl, substituted aryl, aralkyl and substituted aralkyl, and n is an integer from 0 to 3 with about an equimolar proportion of an ammonium halide or hydrazonium halide, and about a 1 to 2 molar proportion of hydrazine hydrate in a composition selected from a C.sub.1 to C.sub.4 aliphatic alcohol, water or a mixture thereof, at a temperature from about ambient to the reflux, and isolating the end product as a monohydrohalide. This invention also provides a process for preparing a 2-hydrazino-1,3-diazacycloalk-2-ene dihydrohalide. The process comprises reacting a compound of the formula: ##STR2## wherein R.sup.1 is hydrogen, C.sub.1 to C.sub.6 alkyl, or C.sub.1 to C.sub.6 hydroxyalkyl, R.sup.2 and R.sup.3 are independently hydrogen or C.sub.1 to C.sub.6 alkyl, n is 0 to 3 and X is a halide ion, with hydrogen halide wherein the halide ion is the same as defined above in a C.sub.1 to C.sub.4 alkyl alcohol at about 0.degree. to 30.degree. C.; and recovering the corresponding 2-hydrazino-1,3-diazacycloalk-2-ene dihydrohalide.