guy
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Nucleophile question
This is probably a very simple question but I can't seem to figure it out. If nucleophiles such as ammonia can attack carbonyl groups and form
amides, why don't they form amides when they attack a metal cation. Like:
NH3 + --CO-- forms --NH2-C-OH--
so why not
NH3 + MO --> MOH(NH2)?
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12AX7
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Probably something to do with the bonds, C=O is covalent while most metal bonds are ionic in nature.
Tim
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guy
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| Quote: | Originally posted by 12AX7
Probably something to do with the bonds, C=O is covalent while most metal bonds are ionic in nature.
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Uh, can you explain more. It would seem to make more sense to form amides if the species were more ionic in character.
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12AX7
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Well, I don't know about the carbon, but for the metal, you'd be looking at probably NH4+(aq) or so interacting with say, M(2+). At best you could
get ionic displacement.
At high temperatures, under dry conditions or else a different solvent, you might get reactions such as MO + NH3 > MN + H2O (unbal). Such occurs
after some time with alkali metals dissolved in liquid NH3, IIRC, although I also seem to remember amines are formed (-NH2 instead of a full reduction
of N(3-)). Eh, after enough time, NH2 should reduce to NH(2-) to N(3-) given an excess of reducing agent.
If you dissolve that in water, I suppose in a manner of speaking you would get "MOH(NH2)", but the OH bit would be due to hydration and better written
like "MNH2.H2O" or so.
But this is just my guess...
Tim
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