Author Topic: DeBrominating 2-bromo-ergo-alkaloids  (Read 14949 times)

0 Members and 1 Guest are viewing this topic.

yogi_

  • Guest
DeBrominating 2-bromo-ergo-alkaloids
« on: October 15, 2004, 12:28:00 AM »
Hello fellow bees!
Ive been lurking around for quite some time, doing some research and all. Ive wanted to post this and get some feedback.
1 recently acquired some 100grams of 2-alpha-bromocriptine mesylate.
The bee has read all about how to debrominate it here on the boards, and thinks drone's method of grignarding t in Mg(s) and then quenching with water would be effective, but some1 pointed out that yields might be low.
Anothre bee suggested the use of HBr, but stated that yields would probably also be low and the isomeric product would be achieved.
So this bee was wondering if anyone can think up a better way to debrominate it?
Here is how the bee is thinking about doing the grignard, if any1 has any comments, please add :
1. hydrolize bromocriptine -> 2-bromo-Lysergic acid
2. 2-bromo-lysergic acid + diethylamine (with pybop) -> 2-bromo-lsd.
3. dry BOL-148 in the vacuum ovev, drop in anhydrous ether+Mg(s), and let react. If reaction doesnt start, put in the ultrasonic cleaner, and sonicate.
4. add H2O after reaction is complete
5. seperate the ether layer, and titrate the lsd out with tartaric acid.
6. chromatograph and rextalize.

Can some1 point out where Ive mastakes?
Also, could 2-bromo-lysergic acid be rexytalized from water much the same as lysergic-acid?
would BOL-148 xtalize out of solution with tartaric acid?

Thanks!


Lilienthal

  • Guest
Check your textbook for the reaction partners...
« Reply #1 on: October 15, 2004, 01:51:00 AM »
Check your textbook for the reaction partners of Gringnard reagents and look if such a group is present in the molecule  :P

yogi_

  • Guest
Mendeleev Communications
« Reply #2 on: October 15, 2004, 06:58:00 PM »
Hi.
Ive foudn this article about debrominating 2-bromo-carboxylic acids, of formula RCHBrCOOH, into RCH2COOH.
Cant read it though. If anyone can link to it or put it here, it will be much appreciated -
DOI:

10.1070/MC1994v004n01ABEH000332


Abstract -
2-Bromo-substituted carboxylic acids (RCHBrCOOH) undergo reductive debromination and form unsubstituted acids RCH2COOH.


Offline Beard

  • Pupae
  • **
  • Posts: 64
  • Yes, it is a beard of bees.
    • Pick a chemistry related ebook or publication you want (see list)
Re: Mendeleev Communications
« Reply #3 on: February 20, 2017, 08:04:45 AM »
Hi.
Ive foudn this article about debrominating 2-bromo-carboxylic acids, of formula RCHBrCOOH, into RCH2COOH.
Cant read it though. If anyone can link to it or put it here, it will be much appreciated -
DOI:<html><body><p>10.1070/MC1994v004n01ABEH000332</p></body></html>
Abstract -
2-Bromo-substituted carboxylic acids (RCHBrCOOH) undergo reductive debromination and form unsubstituted acids RCH2COOH.

Paper attached.