Some Reactions of Nitroparaffins

Excellent comprehensive reviews10 of the chemistry of the nitroparaffins are available elsewhere and it is intended to discuss here only those reactions of aliphatic nitro compounds which have found application in the chemistry of the carbohydrates. 

When a primary or secondary nitroparaffin is allowed to react with an aldehyde in the presence of a basic catalyst, the product is a nitroalcohol. 

The condensation of nitromethane with formaldehyde is not typical of the general reaction since more than one molecule of formaldehyde tends to condense with one molecule of nitromethane even in the presence of a large excess of the latter. When equimolar quantities of formaldehyde and nitromethane are allowed to react the following approximate percentages of the three possible condensation products are obtained 1  

CHiO + CH2N02- CHjOH CHjNOj + (CH20H)2-CHN02 + (CH20H)j CN02 9 percent 13 percent 78 percent 

Even when a five-molar excess of nitromethane is employed the yield of 2-nitroethanol by this reaction is only about 40 percent. With homologs of either nitromethane or formaldehyde the tendency for more than one molecule of aldehyde to condense with one molecule of nitro-paraffin decreases sharply with increasing molecular weight or complexity of either component. 

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