Sciencemadness Discussion Board

Is there an error in this textbook?

killswitch - 7-9-2013 at 14:31

On page 11 of Organic Chemistry of Explosives (J. P. Agrawal & R. D. Hodgson, 2007), there appears to be an error. They show NaOH and Cl2 converting nitromethane to chloronitromethane. One of the references they give (attached below) describes this process with nitroethane to form 1-chloro-1-nitroethane, but I was under the impression that nitromethane in strong aqueous base immediately condenses to the 2-nitroacetate salt.

If it is possible to produce chloronitromethane from aqueous base, would sodium hypochlorite serve as a workable chlorinating agent?

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AndersHoveland - 7-9-2013 at 15:41

No, it is not an error. In fact, chlorination of nitromethane with hypochlorite results in chloropicrin (trichloro-nitromethane).

The ratio of reactants may be important here. Chlorine is known to react with hydroxide to form hypochlorite. And I would suspect that monochloro-nitromethane is not stable for long in the presence of excess base.

Quote: Originally posted by killswitch  
would sodium hypochlorite serve as a workable chlorinating agent?

Hypochlorite is probably the best chlorinating agent here.

In case you did not know, there is always some hydroxide ions and free chlorine in equilibrium in aqueous hypochlorite solutions.

Just realize that chlorinated nitromethane is a potent lachrymatory agent, and chloropicrin fumes are rather poisonous.

[Edited on 7-9-2013 by AndersHoveland]

killswitch - 7-9-2013 at 20:59

Quote: Originally posted by AndersHoveland  
In case you did not know, there is always some hydroxide ions and free chlorine in equilibrium in aqueous hypochlorite solutions


That's why I suggested it. Reading the paper made me wonder why they went to the trouble of constructing special apparatus to pump chlorine into alkaline media.

I still wonder to what extent condensation would compete with chlorination.