[Cheese_Burgers]

So, I'm interested in understanding what is happening when I dissolve pyridine and Phenol in DCM as the first steps to an acid chloride acyl substitution I'm doing.

I'm trying to understand if the phenol is deprotonated during this initial step or if it's not energetically favorable. No salts fall out of solution so i'm kind of confused. I've deduced 3 possibilities:

a)deprotonation does not occur because the products are not energetically favorable in the NP solvent.
b)deprotonation occurs, they form an ionic bond with each other, and the large NP protions of phenol and pyridine are what keeps them in solution.
c)deprotonation occurs, they do not form an ionic bond and just float around in solution as charged ions as permitted by their NP regions.

Now, Ive done this reaction in solvent free conditions by co-grinding phenol, the acid chloride, and NaOH, and HCl gas is Generated. So, this leads me to beleive that deprotonation does not happen in my initial step of the reaction in DCM and that the protonated phenol is my nucleophile which attacks, followed by the generation of HCl gas, which the pyridine immediatly neutralizes.

I hope this is clear enough.

Also, I'm running this reaction with 2 eq. of the pyridine but I cant determine why...

Thanks for any  responses!

[Babcock_Hall]

A good place to start is to look up the pK_a values of phenol and pyridine.  However, they are unlikely to be exactly the same values in DCM.