I thought that the Zn/An formate rdxn of nitro compounds was something similar to the classic Zn acetic one. Then Rhodium posted another reference wich uses zinc and hidrazinium monoformate, very similar to this one, so I decide to try it and see what happens.
Initially I checked adding Zn to a solution of ammonium formate and methanol, and it makes nothing. Then I added nitromethane and zinc to methanol and then added the formate, and as sonn as it came in solution started a energic, exhothermic and effervescent reaction. The same, but immediatly, happened when the zn was added to a solution of nitromethane and ammonium formate in methanol, disappearing completely the Zn, wich was not pretreated with diluted HCl (but good quality one).
In conclusion I was wrong, but my doubts about the amount of reactants still persist. They use 0.6 mmol of Zn and 0.8 mmol of formate to reduce 0.5 mmol of nitrocompound, my best numbers are that the formate could decompose giving 0.8 mmol of H2 and the Zn could react with the NH3 producing 0.6 mmol of H2 more, 0.14, but it is necessary 0.15 for a 100 % efficiency. Furthermore, when formic acid is used instead of the formate, the Zn disappears, so I think it reacts forming the formate.
Any light about the mechanism of the reaction ?
