vinothan23
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Reaction of triethylamine with hydrogen fluoride
what is the reaction of HF with Triethyl amine in detail?
[Edited on 17-2-2012 by ScienceSquirrel]
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simba
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HF forms a fluroride salt with triethylamine. Acids form salts with amines.
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BromicAcid
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Not that easy, triethylamine forms a number of salts with hydrogen fluoride, the most common of which that I run across is not the
(CH<sub>2</sub>CH<sub>3</sub> <sub>3</sub>N*HF
that you would expect but the trihydrofluoride salt (CH<sub>2</sub>CH<sub>3</sub><sub>3</sub>N*3HF which is commonly used in fluorinations or as a catalyst in fluorinations. As for the
detailed mechanism, not sure.
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Hexavalent
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Should this not be in Beginnings?
"Success is going from failure to failure without loss of enthusiasm." Winston Churchill
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ScienceSquirrel
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Thread Moved
10-2-2012 at 16:32 |
ScienceSquirrel
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Honestly yes.
Hydrogen fluoride forms strong hydrogen bonds so it is to be expected that species like (Et)3N.3HF are formed.
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Hexavalent
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Also, I would suggest adding a more descriptive title in the future . . .
"Success is going from failure to failure without loss of enthusiasm." Winston Churchill
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arsphenamine
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Honestly, I don't understand.
SF<sub>6</sub> gives you d-orbital contributions to explain the hypervalence but no such orbitals are available with nitrogen.
Is this an instance of hyper<i>coordination</i> primarily due to HF species hydrogen bonding amongst themselves?
I'll model it, let you know if it's interesting.
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ScienceSquirrel
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Here is an interesting starting point;
http://benthamscience.com/open/tospecj/articles/V005/26TOSPE...
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arsphenamine
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Thanks for the impressively pertinent reference.
I've had time to model the Et3N:3(HF) compd.
Semi-empirical methods (MOPAC, PM6) are extremely sensitive to the starting geometry, and no use other than for generating an input for ab initio
methods.
Successively refined ab initio comps produce a geometry you'd expect if you focused on the H-bonds, but (perhaps fortuitously) give an N-H-F bond
length of 2..586A in good accord with the 2.60A in Ilayaraja, et.al. NMR spin relaxation experimental methods.
GAMESS-US eq. geom. at the RHF/631G(2dp)** theory/basis set level were translated to Z-matrix format for Avogadro display and then exported to a .PNG
image.
As expected, nitrogen is completely protonated.
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