April 20, 2024, 02:26:41 AM
Forum Rules: Read This Before Posting


Topic: TMSBr distillation  (Read 4574 times)

0 Members and 1 Guest are viewing this topic.

Offline Kaladiscope

  • Regular Member
  • ***
  • Posts: 60
  • Mole Snacks: +0/-0
TMSBr distillation
« on: August 06, 2012, 07:20:15 PM »
Hi,

Are any of you familiar with the distillation of TMSBr?

I want to distillate it, in order to make if free of water and therefore of HBr and I would really appreciate any suggestions or any procedure to go on.

Thanks in advance,

Offline OC pro

  • Chemist
  • Full Member
  • *
  • Posts: 396
  • Mole Snacks: +36/-15
  • Gender: Male
Re: TMSBr distillation
« Reply #1 on: August 07, 2012, 02:43:59 AM »
Boiling point is 79°C. I would distill under atmospheric pressure under argon or nitrogen atmosphere. No problem.

Offline PhDoc

  • Full Member
  • ****
  • Posts: 133
  • Mole Snacks: +22/-0
  • O-Chem Prof
    • PH.D. Organic Chemistry Tutor
Re: TMSBr distillation
« Reply #2 on: August 09, 2012, 12:42:27 AM »
Distilling it is no problem, getting it HBr free is a challenge. Everything has to be bone dry, however not even that's enough. Below is a trick I used for ester enolate Claisen rearrangements.

Distill TMSCl fresh. Take a known aliquot, then carefully add to a known volume of Et3N. Centrifuge down the Et3NHCl precipitate. Supernatant contains acid free TMSCl.
O-Chem Prof

Offline james_a

  • Regular Member
  • ***
  • Posts: 43
  • Mole Snacks: +6/-0
Re: TMSBr distillation
« Reply #3 on: August 09, 2012, 10:50:37 PM »
Hi,

Are any of you familiar with the distillation of TMSBr?

I want to distillate it, in order to make if free of water and therefore of HBr and I would really appreciate any suggestions or any procedure to go on.

Thanks in advance,


Assuming you're doing an ether cleavage, why don't you just make TMSI in situ? Treatment of readily purified TMSCl with NaI in acetonitrile is very effective.

Offline Kaladiscope

  • Regular Member
  • ***
  • Posts: 60
  • Mole Snacks: +0/-0
Re: TMSBr distillation
« Reply #4 on: August 13, 2012, 04:28:45 PM »
Lennoxtutoring:

what u said sounds amazing! I will give a try!

OC pro:

Distillation under argon atmosphere and heating at 79 ºC...I just heard that u need also special conectors...

Offline Babcock_Hall

  • Chemist
  • Sr. Member
  • *
  • Posts: 5609
  • Mole Snacks: +321/-22
Re: TMSBr distillation
« Reply #5 on: August 22, 2012, 10:29:31 AM »
I have refluxed TMSCl prior to distillation, but I have never tried using triethylamine.  Interesting.

Sponsored Links