Guanidine-formaldehyde condensations

Diazomethane (called Diazomethan in Ger), C cNiN mw 42.04, N 66.64% poisonous yel gas condensing to a yel liq, bp -24 to -23° and solidifying in pale-yel crysts, fr p -145° explodes violently when heated to a higher temp sol in eth more important methods of prepn are from nitrosomethylurea, nitroso-methylurethane, a mixt of chloroform fit hydrazine hydrate, or l-methyl-l-nitroso-3-nitro-guanidine by reaction with KOH from nitrosyl chloride methylamine by treatment of the Na salt of formaldehyde oxime with chloramine and by other methods... 

Suitable blending of ammonium salts of fairly strongly basic amines (e.g., melamine or guanidine) and acid condensation with formaldehyde enables favorable conditions to be obtained with regard to solubility and cross-linking of the cationic condensation resins. 

---