The attached article may answer some of your questions:

Reduction of Schiff Bases with Sodium Borohydride
JOHN H. BILLMAN , ARTHUR C. DIESING
J. Org. Chem., 1957, 22 (9), pp 1068–1070
DOI: 10.1021/jo01360a019
Publication Date: September 1957

More information about this subject can bee found at:

https://the-collective.ws/forum/index.php?topic=9873.0

which has been posted on this web site before     The end results from the effort applied 

The only thing that confuses me about LabTop's NaBH4 write up is that he seems to have a tank of anhydrous MeNH2(g) with a valve lying around.

All of my attempts to gas IPA with methylamine varied wildly in their effectiveness. I do think I was lacking a few pieces that were crucial (cannulas, septums, dispersion tubes etc.) Sometimes I could get sub zero IPA up to high concentrations within minutes, and other times several gassings would only trap a few grams.

I think this reaction would work for you using your solution in abs EtOH though. It's worth a shot on a small scale for sure.

I need to make some more MeNH2 and practice gassing some cold MeOH.

So this is what happened. I still don't know what to make of it since the reaction is still running.

I used more methanol and methylamine than Labtop, since the scale was small. I just kept almost the same concentration of mathylamine in the alcohol. I increased the Methylamine solution in methanol by a factor of 1.6

I used the follwing:

10g MDP2P (don't know the purity, from a buffered performic. it's pale yellow with some hint of green I vacuum distilled it @75-84°C and it creates a xtalline precipitate with sodium bisulfite, maybe some oil emulsion stays on top of the xtallised bisulfite solution) Only doubt I have on this ketone is that when the distillation started it seemed transparent and then gradually became more yellow. the last drops condensing in the column seemed more intense yellow. Is it possible that the higher the temp the more intense the yellow color gets? or is there some isosafrole in there?

38ml methanol (30g)
15g 33% methylamine solution in abs ethanol. (i.e. 5g methylamine)
5-6g silica gel beads (regular white, dried in oven @130°C for 4 hrs)

I dried some silica gel in the oven @ 130°C. not 300°C since I didn't want it to turn it brown.I read that the lower temp should work anyway. Everything below is done with stirring.

I dried the methanol first with some other silica gel and then filtered it and mixed it with the methylamine in abs ethanol with more silica gel. To this the ketone was added slowly even though the flask (immersed in 20°C water) did not seem to increase in temp.  The imine formation did not seem eventful (did it ever form? just a little color change, pale yellow became less yellow and more opaque yellow).

After 1 hr I filtered the silica, washed it and put everything in another small RBF. I stared adding the NABH4 in portions (i was running 10g MDP2P). At each addition, apart from the last few ones, temp increased from 7°C to 15°C with some gas evolution. I waited for it to go down before adding again.

Tonite (at the 24hrs mark), I will flood the reaction with water and see if anything precipitates. What I don't understand is that I didn't see any sort of major color change. maybe it's just getting clearer, but I cannot really tell to be honest as it was also diluted with some methanol along the reaction.

I read in other people's posts about coffee + milk colored imine, orange imine...Mine had little color change and it was never cluody. Is the reaction supposed to change in color during the reductive amination? I will surely run an a/b after I isolate whatever oil separates at the end and see if there is some kind of amine, but in the meantime I d appreciate some comments. Was it maybe a problem with my silica not dry enough? Should i maybe use drying salts next time or get hold of 3A mol sieves? any inputs?

I'm really anxious to get my hands on some NaBH4 so I can run some experiments with this reaction as well. I wish I could be of more assistance.

I'm curious though... did you say your ketone distilled at 75-84c?  did you mean 175-184c?

_Pbint_

He probably did mean what he posted. I recall seeing elsewhere him talking about a pretty decent vacuum pump he acquired.

although I am confused. NaBH4 should not react with water in a basic solution. It is even sold as water solution. So when I added it to the methanolic imine it should not react with the water, since the solution is basic. so the gas evolution Gas evolution was vigorous.I am gettin lost here

This may all be academic, have you worked up your post reaction solution yet? Post your results

Would it be a good idea next time to form the imine in 33% methylamine ethanol solution an later add methanol just before starting the reduction by addition of borohydride?

Ok guys, finally some updates. I worked up the reaction as I said I would in my earlier post:

I washed the oil in DCM with 10% aq. NaOH two times to get rid of the methylamine. I then proceeded to extract the DCM layer with 10% HCl to make sure I was extracting only amines. I then  based my aq. HCl with 10% NaOH and got some beautiful light golden oil precipitation and it also seemed a lot. I extracted my amine oil in DCM 2 times, added some MgSO4 to take up the water then filtered it out a and washed it with some clean DCM to minimize losses.

I then boiled off DCM under aspirator reduced pressure. I ended up with a little less then 9 grams of MDMA oil from 10g ketone. That is I believe in the range of 83% molar yield. I did not distill the freebase though.

I didn't want to assemble a proper gassing rig so I the weighted the correct amount of 37% HCl, dissolved the FB oil in 6 times its volume in acetone (dried with MgSO4) in an Erlenmeyer flask, cooled everything in an ice bath and pipetted in the 37% HCl, while progressively checking the ph of the acetone with wet ph paper.

In the end I had to add all of the weighted HCl to get ph down to around 5. The flask was then stoppered and put in the freezer to complete precipitation. It will be soon filtered and reduced (or diluted with a non polar like hexane or toluene) to get the remaining salt out.

Below is a picture of the flask. It's not too clear but you can see the xtals below.

I saved the non basic oil diluted in the DCM which I had left from my workup. I tried adding some freshly made bisulfite solution to some of that DCM to see if something was precipitating but I got nothing. I presume some ketone was reduced to the alcohol or was not properly distilled after the performic.

I will double check my ketone distillate to make sure that is not the issue and I will try drying my methanol before the reduction with MgSO4 and filter out the solids. Would that be beneficial of would it interfere with the NaBH4 it being a little acidic?

I was also thinking to prepare the imine just with ketone and 33% Methylamine in Ethanol at low temp, then after 2-3 hours adding the dried methanol and start reducing with NaBH4. What do you think about it?

Anyway I am very glad this turned out to be good

Yeh good work hero.

This self sufficient thing is coming along quite nicely.

What's next?