Natural Science Forum / Chemistry / Organic Synthesis / February 2006

I would quite naively suggest to react nitroguanidine with formaldehyde
under acidic catalysis.

Be careful!

The stuff could explode.

Best regards.

Gabriel Tojo

Consultant in Organic Synthesis

Hi mr gabriel,

   Did the same with the following conditions

2 times the momlar amount of Formalin
nitroguanidine,
Methyl nitrite gas in methanol solvent and dry HCl gas in the reacn
mixture. But itt didnot fare anyresults. Please help.

Thanks
Jyot Vakharia

Methanol is not a good choice as solvent because it reacts with
formaldehyde resulting in the formation of CH2OMe2.

Dry HCl is fine, but I do not understand the purpose of methyl nitrite.

Formalin, that is, an aqueous solution of formaldehyde, coulf not have
been a good choice because it contains plenty of water. Although, I am
not very sure about this point. Perhaps some water would not make any
harm.

Perhaps it is better to use a certain excess of formaldehyde, either
gaseous, which is inconvenient, or as paraformaldehyde or something
similar.

I would try the reaction in an organic acid like AcOH or HCO2H and I
would bubble formaldehyde in a solution of nitroguanidine in that
solvent. If it does not react, I would heat gently. If it keeps on not
reacting, I would add a small amount of a strong acid like gaseous HCl,
which I hate in the lab,  H2SO4, TsOH, MsOH or TfOH. Then I would
increase slowly the quantity of acid till something happens.

And, for God?s sake, please, avoid using gaseous HCl, unless absolutely
necessary. Your health is more important than the experiment.

I think that formaldehyde under acidic conditions is the right thing to
do. You need to persevere before giving up.

Good luck

Best regards.

Gabriel Tojo

Consultant in Organic Synthesis