April 16, 2024, 05:04:41 PM
Forum Rules: Read This Before Posting


« previous next »
Pages: [1]   Go Down

Topic: Which are the most acidic ?  (Read 5640 times)

0 Members and 1 Guest are viewing this topic.

Offline shalikadm

  • Full Member
  • ****
  • Posts: 115
  • Mole Snacks: +4/-10
  • Gender: Male
  • smells like isopropyl alcohol
Which are the most acidic ?
« on: June 22, 2012, 03:18:32 PM »

In the first one there's two deactivators while the second one has only one.But the second one has more electronegative element F as the deactivator..So how can I choose the most acidic ?
Logged

Offline Nescafe

  • Full Member
  • ****
  • Posts: 346
  • Mole Snacks: +7/-11
Re: Which are the most acidic ?
« Reply #1 on: June 22, 2012, 03:42:46 PM »
I would say the dichloro due to the fact that the electronegativity of F is about 4.0, that of Cl is 3.0. There is one unit difference but there are two Cls v.s. one F. I do not think they are much different though.
Logged

Offline orgopete

  • Chemist
  • Sr. Member
  • *
  • Posts: 2636
  • Mole Snacks: +213/-71
    • Curved Arrow Press
Re: Which are the most acidic ?
« Reply #2 on: June 22, 2012, 06:43:09 PM »
The chloropropionic acid should be more acidic. I compared the dichloro with monofluoroacetic acids and the dichloroacetic acid was more acidic, 1.29 vs 2.66, see http://research.chem.psu.edu/brpgroup/pKa_compilation.pdf

Logged
Author of a multi-tiered example based workbook for learning organic chemistry mechanisms.

Offline cheese (MSW)

  • Not a
  • Full Member
  • ****
  • Posts: 144
  • Mole Snacks: +15/-23
  • Gender: Male
Re: Which are the most acidic ?
« Reply #3 on: June 23, 2012, 12:26:41 PM »
CH3CCl2CO2H 2,2-dichloropropionic acid   pKa = 1.68
CH3CHFCO2H  2-fluoropropionic acid    pKa = 2.68
CAS
Logged
Pages: [1]   Go Up
« previous next »
Sponsored Links