It seems that there's no way to make the work up more optimized, doubts with NH3 and furthermore, to work with lots of NH3 is terrible.
I've tried my idea of adding alcohol to precipitate the hydroxides and it didn't work with reeasonables amounts of it, so I fucked the work up. I evaporated part of the methanol and tried toluene to extract and I have emulsions that slowly separates, I can finish it but need more time. The final basic solution with not all hydroxides dissolved is about 1700 ml, for 10 grams...
Bandil, if you want to try this rxn, I propose you this:
Make a solution of 12 water, 36 methanol (IPA) and 8 HCl 36 %. When it si at 25 C add 10 grams of powdered nitro (coffe grinder) and stir. At 25-30 add 60-70 grmas of Zn and 213-251 HCl 36 % , with the first 30 grams add 33 ml of HCl and with the rest 38 ml of HCl, the idea is to add 3.3 ml for each gram in the first 30 grams and 3.8 ml with the rest, in small portions. You can make it as you want, but try to keep this adition ratio and add all in about 2-3 hours. Keep the temp ok and don't add small portions specially in the beginning, you can use a big syringe for the HCl or it you have and ad. funnel, of course. Then let stir 4-8 hours, or less if all is dissolved, and probably you'll have a bit of Zn-thing undissolved in a transparent slightly yellow solution.
Unfortunately it can be washed with DCM because the similar density and toluene doesn't remove too much, but make 2x20 toluene, add enough NaOH 25% cooling to dissolve if not all the most of the hydroxides and you'll have a big solution-suspension to extract, wash the extracts wihh NaOH 25 %, brine, dry and xtallize.
The initial solution is small in order to keep the HCl conc. in an adequate range adding less HCl to finish with a smaller volume, but the density is so high that DCM doesn't work.
If you only have HCl 30 % use PM and I'll give the adequate ratios, I've it in Excel.
Good luck and tell us what happened. You got some carbonate of the amine in your first attempt. If you evaporate all solvent it is formed realily. When you finish the work-up you see carbonates in any flask where the solventeĀ with the amine has been.