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I would like to know which of the two is the stronger base, tri-(n-butyl)amine or tri-(tert-butyl)amine?

I feel that the one with tert-butyl would be stronger as the inductive effect of tert-butyl on the nitrogen atom is stronger, making the nitrogen atom more electron-rich and better able to act as a base. This is because the carbon atoms in tri-(tert-butyl)amine are closer to the nitrogen atom, with the furthest carbon just 2 carbons away. However, for the other amine, the furthest carbon is 4 carbons away. I am not sure if my reasoning is flawed. Could someone clarify?

I am also not sure if steric hindrance is an important consideration here, considering the bulkiness of the tert-butyl substituent compared to the n-butyl substituent.

Also, pardon me if I had written the names of the chemicals wrongly.

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  • $\begingroup$ Your reasoning is fair. This seems to list most of the amines and its dissociations with some useful info However don't forget any steric hindrance that could degrade the (alkyl contributed) electrons releasing ability of tert-alkyl amine's N (because alkyl is larger than H+ atom). Last but not least solvation of ions is a must to consider due to the ability to form Hydrogen bonds. a bit like catch 22 case :P $\endgroup$ – bonCodigo Jul 23 '17 at 12:32
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    $\begingroup$ Tri-(tert-butyl)amine has never been synthesized, so this is more of a theoretical study. $\endgroup$ – AS_1000 Jul 25 '17 at 11:06
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    $\begingroup$ I learned that Hünig's base was the strongest one available. $\ce{N(tBu)3}$ is probably too crowded to even exist. $\endgroup$ – Martin - マーチン Jul 25 '17 at 11:47
  • $\begingroup$ @Martin-マーチン Assuming if it exist. This question has actually been taken off an inorganic chemistry textbook. However, the answer was not provided. Therefore, I had to pose this question on this platform. $\endgroup$ – Tan Yong Boon Jul 26 '17 at 9:47
  • $\begingroup$ @Martin-マーチン A friend of mine mentions that steric hindrance only affects kinetics. Since I am only considering thermodynamics, in terms of equilibrium, can I safely put it out of the discussion? Or should I still consider it? $\endgroup$ – Tan Yong Boon Jul 26 '17 at 9:49

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