April 27, 2024, 11:35:43 AM
Forum Rules: Read This Before Posting


Topic: Question about HMBC  (Read 2782 times)

0 Members and 1 Guest are viewing this topic.

Offline bonkers

  • Regular Member
  • ***
  • Posts: 12
  • Mole Snacks: +0/-0
Question about HMBC
« on: January 19, 2015, 03:35:53 AM »
Hello

Can anyone explain why don't protons numbered "7" in 3,4-diaminoanisol give any HMBC crosspeaks? I'm not even sure which ones are "7"
1) 3.98 in the spectrum
2) 3.44 and 3.98 in spectrum and the integrals are bigger because of impurities
3) 4.50 (same as "8") but the integral is just smaller

Spectra:
1H

HMBC(green) HSQC (red)


Offline Irlanur

  • Chemist
  • Full Member
  • *
  • Posts: 423
  • Mole Snacks: +32/-4
Re: Question about HMBC
« Reply #1 on: January 19, 2015, 06:37:32 AM »
conditions? (eg solvent?)

Offline bonkers

  • Regular Member
  • ***
  • Posts: 12
  • Mole Snacks: +0/-0
Re: Question about HMBC
« Reply #2 on: January 19, 2015, 07:45:17 AM »
conditions? (eg solvent?)
40 mg in 0.6ml DMSO

Offline Babcock_Hall

  • Chemist
  • Sr. Member
  • *
  • Posts: 5610
  • Mole Snacks: +321/-22
Re: Question about HMBC
« Reply #3 on: January 19, 2015, 09:29:45 AM »
It is a forum rule that you must show your attempt at solving a problem before we can help.  What hydrogen atoms should or should not show up in the HMBC in theory?

Sponsored Links