A novel heterocyclic system-dihydro-2H-l,5,2,4-dioxadiazine.2,4-Dimethyldihydro-2H-1,5,2,4-dioxadiazine hydrochloride:synthesis and NMR study

摘要

The first representative of a novel heterocyclic system,namely,2,4-dimethyldihydro-2H-1,5,2,4-dioxadiazine hydrochloride,was synthesized.Construction of the 1,5,2,4-dioxadiazine ring has been reported only for two 2,4-dialkyl-2H-l,5,2,4-dioxadi-azine-3,6(2,4H)-diones.Data for dihydro-2H-l,5,2,4-dioxadiazine or its derivatives have not been documented to date.Our approach to the synthesis of the target structure was as follows(Scheme 1).Bis(aminooxy)methane(l)may be regarded as a heteroanalog of 1,3-diaminopropane,which is known to form hexahydropyrimidine in the reaction with formaldehyde.5-6 An analogous reaction of bis(aminooxy)methane should give dihydro-2H-l,5,2,4-dioxadiazine 5.