The Formation Pathway of 3,5-Bis(methoxymethyl)perhydro-1,3,5-oxadiazin-4-one

Abstract The investigation of the reactions of urea and its methyl derivatives with formaldehyde elucidated the formation pathway of 3,5-bis(methoxymethyl)perhydro-1,3,5-oxadiazin-4-one. 1) The addition of formaldehyde to urea became increasingly difficult according to the increase of the number of added formaldehyde molecules, probably because of the steric hindrance of the hydroxymethyl groups. 2) 3,5-Bis(methoxymethyl)perhydro-1,3,5-oxadiazin-4-one was concluded to be derived from urea via tris(hydroxymethyl)urea and 3-(hydroxymethyl)perhydro-1,3,5-oxadiazin-4-one but not via tetrakis(hydroxymethyl)urea or perhydro-1,3,5-oxadiazin-4-one.