xwinorb
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Nitromethane
I have the impression that one of the bonds between the N and O in the nitromethane molecule is a dative bond, is this correct ?
Also looks like it is slightly polarized ? I see one + and one - sign on the N and O atoms.
Looking under nitromethane in the Wikipedia.
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JohnWW
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Yes; same with all organic nitro compounds, C-NO2. There is a positive charge on the N atom; and the negative charge alternates by resonance between
the two O atoms, giving an average 1½ bond order.
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turd
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Since electrons are not "owned" by an atom, the concept of dative bond is overrated, if not useless. Maybe it has some relevance for the electron
counters (i.e. complex chemists).
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ScienceSquirrel
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It can be convenient to think of a nitro group this way when using resonance structures to justify the acidity of the protons on alkyl nitrates or the
ease with which 2,4,6-trinitochlorobenzene undergoes nucleophilic substitution.
It is only a model of the real situation but it does have useful predictive results and it is easily understood and used on paper.
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DJF90
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Nitromethane is not that dangerous; there is no need to try and scare people. And what do you mean "definately aren't cut out for making at home"? I
think its a perfectly reasonable synthesis to perform, and nitroalkanes are useful synthons in that they allow ready formation of carbon-carbon bonds,
much like malonate and acetoacetate esters. Add to that the general synthetic utility of the nitro group (reduce to amine, Nef reaction to ketone,
further nucleophilic action of the a-carbon etc...) and you've got yourself a versatile material.
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entropy51
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Quote: Originally posted by arnoldclab  | | It's important to note that most of these methods are pretty risky...and definitely aren't cut out for making at home. |
That would be news to those here who do it all the time, without loss of life, limb or property.
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