Methylamine hydrochloride

Methylammonium chloride aka methanamine hydrochloride, methylamine hydrochloride or just aminomethane hydrochloride, is an interesting compound with the formula CH5N.HCl. I plan to use my sample to make methyldichloramine and possibly N-methyl-2-propanimine. This is how I made it:

I started by pouring some powdered hexamethylenetetramine into a 1L flask. I then poured an excess of dilute hydrochloric acid and quickly corked the flask. I shook the flask and noticed a lot of fumes and white smoke being produced in the flask. Once the smoke had redissolved I saw that all the hexamethylenetetramine had dissolved. I left the corked flask to stand overnight and in the morning I noticed there was a crystalline precipitate of ammonium chloride in it. I transferred the mixture to a round bottom flask and setup for reflux. After the mixture had been refluxing for about 4 minutes I noticed the ammonium chloride redissolved. In total I refluxed the mixture for about 2 hours and after this I noticed it was slightly yellow (this is due to a dimethylamine impurity).

Next I started boiling down the mix and as soon as lots of crystals of methylamine hydrochloride and ammonium chloride started precipitating I turned off the heat. I filtered out the crystals and quickly dried them. Next I added boiling ethanol to the crystals.

Methylamine hydrochloride is very soluble in ethanol whereas ammonium chloride is rather insoluble. I filtered again discarded the insoluble ammonium chloride. As for the filtrate solution of the product, I boiled it down in a water a water bath until I was left with small white crystals of methylamine hydrochloride. I repeated this process (boiling down the mixture, filtering the crystals, adding boiling ethanol etc. until the reaction mixture was consumed. I noticed sometimes my product was yellow. I just washed the yellowness out with very cold ethanol and I was left with a relatively pure product: