Preparation and characterization of hexamethylenetetramine N-oxide and some acid adducts

Hexamethylenetetramine N-oxide (4) was isolated from the reaction of hexamethylenetetramine (1) with 30% aqueous hydrogen peroxide. With the two reactants in molar ratio 1 : 2, a 1 : 1 : 1 crystalline adduct (5) of (4) with hydrogen peroxide and water was obtained at temperatures around 10°C, and a 1 : 1 adduct (6) of (4) with formic acid upon warming the reaction mixture to above 30°C. Information pertaining to the nature of compounds (4), (5) and (6) was derived from p.m.r, and X-ray determination of unit cells and space groups. Several 1 : 1 acid adducts similar to (6) were prepared by adding the corresponding acid to an ethanolic solution of (4).