Hi Hest,
Thanks for the comment.
SWIM has read it many times, during SWIM's meals too. SWIM will try bandil's mol sieves method once he gets the methylamine solution.
As for the method outlined, without PTC, the amount of each chemical used is very sensitive towards the resulting yield. Eg, the amount of H20 used is the major thing, if the solution is not salty(concentrated) enough, not enough methylamine gas is pushed to the IPA, thus affecting yield. If the NaBH4 used is slightly more, the water is not able to dissolve all. SWIM has got extreme low yield(range from 0% to 10% m/m if you wanna know) when using a mechinical weighing machine which is not very sensitive to weighing things at 10g scale. SWIM purchased a digital weighing machine, with 0.1g increment. All followed to the letter outlined in the post. Yield was around less than 15%. SWIM was very happy and that was some improvement. SWIM tried to use IPA 91%(all previous used was 99.7% claimed by manufacturer), highest yield was about 40%. SWIM has tried to vary the method to give optimum output but failed. Oops, SWIM is not going to declare it fail yet. SWIM will try until he gets good result, with repeatability.
Now, SWIM has planned to use other solvent, toluene is in the list, ethanol, DCM, DMF are some others. SWIM has no experience with PTC at all, thus the previous post.
Please forgive SWIM's lack of knowledge and asking a lot of stupid quetions.
By the way, did you(hest, hive addickt) produce the same result using aq. solvent? If yes, can you please be kind enough to share what are the tips in achieving the mentioned yield. SWIM firmly believe that it is achievable, thus has performed so many aminations.
Anyway, SWIM has replaced the IPA method using methanol as solvent, generating methylamine gas in situ. Has got his yield shoot up.