November 24, 2024, 04:30:10 PM
Forum Rules: Read This Before Posting


Topic: ortho v. meta v. para NMR for fluorotoluene  (Read 1305 times)

0 Members and 1 Guest are viewing this topic.

Offline karatekboy123

  • Very New Member
  • *
  • Posts: 1
  • Mole Snacks: +0/-0
ortho v. meta v. para NMR for fluorotoluene
« on: March 03, 2020, 12:33:49 AM »
I understand that the c13 NMR would have a different number of peaks between the para and ortho/meta compounds, but how would one distinguish the ortho/meta compounds using either c13 or 1h NMR?

Offline AWK

  • Retired Staff
  • Sr. Member
  • *
  • Posts: 7976
  • Mole Snacks: +555/-93
  • Gender: Male
Re: ortho v. meta v. para NMR for fluorotoluene
« Reply #1 on: March 03, 2020, 03:54:06 AM »
Did you check Molbase.com
AWK

Offline wildfyr

  • Global Moderator
  • Sr. Member
  • ***
  • Posts: 1776
  • Mole Snacks: +203/-10
Re: ortho v. meta v. para NMR for fluorotoluene
« Reply #2 on: March 03, 2020, 10:41:19 AM »
Fluorotoluene isomers have published spectra you can track down. SDBS might also be a good resource.

Generically though, it can be more difficult to determine ortho vs meta in a "new" molecule. Often you have to carefully parse the peaks and determine J values, use 2D NMR, and just generally try harder.

Offline Babcock_Hall

  • Chemist
  • Sr. Member
  • *
  • Posts: 5705
  • Mole Snacks: +330/-24
Re: ortho v. meta v. para NMR for fluorotoluene
« Reply #3 on: March 03, 2020, 11:25:07 AM »
I understand that the c13 NMR would have a different number of peaks between the para and ortho/meta compounds, but how would one distinguish the ortho/meta compounds using either c13 or 1h NMR?
One good resource for general NMR information is CHM 605 at the University of Wisconsin, Department of Chemistry.
https://www.chem.wisc.edu/areas/reich/chem605/

Offline hollytara

  • Chemist
  • Full Member
  • *
  • Posts: 317
  • Mole Snacks: +39/-0
Re: ortho v. meta v. para NMR for fluorotoluene
« Reply #4 on: March 03, 2020, 11:47:11 AM »
If you have an IR, the aromatic overtones just under 2000 cm-1 can distinguish o-m-p

Offline kriggy

  • Chemist
  • Sr. Member
  • *
  • Posts: 1520
  • Mole Snacks: +136/-16
Re: ortho v. meta v. para NMR for fluorotoluene
« Reply #5 on: March 05, 2020, 12:12:20 PM »
para vs others: think about the symmetry in the molecule and should be fairly obvious

ortho vs meta: the splitting patter in 1H is going to be quite different.

Sponsored Links