We went to the house of a friend some days ago and we made a bit of the nitropropene from iso, with the nitrosite procedure. It was the first time for us, and the final product had a strange smell that remebered me other smells and make me think that the product was not pure. The rxn went exactly like with 25DMNS, but always with that strong smell in the flask. We made a TLC MeOH:NH3 of the rxn mixture, with 2,5 DMNS I have observed that there's a big spot at the bottom, probably all Zn salts, and a single spot a bit higher corresponding to 2CH, in this case we forgot the TLC and solvent arrived to the top, so when we rembered it some time later, we saw the spot in the bottom and a single spot, but rf was around 0.6 instead of around 0.2, and we don't know if this diference can be explained due our forgetfullness, if it was the amine, the rxn worked really well.
When finished, and aliquot was basified with 40 % NaOH and clearly appeared drops of oil floating, but I couldn't recognize the smell of amine due the strong persistent smell of the beginning and I had to come back home. After almost two weeks he have not tried xtallization, but he has told me that pH of dried solvent is not significatively basic. Too much time to process it, he should end work up the same day, now everything can be destroyed, I'm dissappointed, he works really ssllllooooowwwwwww. The rxn went apparently pefect, so I would say it worked, but I was not there in the work up and my friend is not really experienced, may be he made a mistake or may be it did'nt work.
I made at home a very small test with 3,4,5 TMPNP, the rxn worked the same, dissapearing the insoluble nitro when Zn was 2-3:1, and basifying appeared the oil with the characteristic amine smell. I'm optimistic, but I can't state it works, and I won't try it at the moment, so if you can, it would be nice to make a small test with 34MDPNP.
I would start with a 5 % HCl in the flask and I would end with a 9 % based in free HCl over total weight, 2 hours addition, better 7:1 Zn, and then evaporate alcohol with aspirator, add water to have a density that let work DCM wash (d~1.2), basify with NaOH 40 + % to reduce volumes, extract... If you want precise details, PM me.