The Vespiary

The Hive => Tryptamine Chemistry => Topic started by: Bubbleplate on September 19, 2004, 08:42:00 PM

Title: Diethylamine - What Molar Amounts Required?
Post by: Bubbleplate on September 19, 2004, 08:42:00 PM
In the original "N,N-Carbonyl diimidazole" process for making LSD, (see

Post 395675 (https://www.thevespiary.org/talk/index.php?topic=12581.msg39567500#msg39567500)

(Rhodium: "English translation (Yield of LSD freebase 57.5%)", Tryptamine Chemistry)
) almost equi-molar amounts of Lysergic Acid and Diethylamine were used:
"(5mmol) anhydrous D-Lysergic Acid... was mixed with… a solution of 0.40g (5.5mmol) Diethylamine in 5ml DMF”.
Yet, the same procedure listed in various new Patents (see

Patent US6476199 (http://l2.espacenet.com/dips/viewer?PN=US6476199&CY=gb&LG=en&DB=EPD)

and

Patent US6063908 (http://l2.espacenet.com/dips/viewer?PN=US6063908&CY=gb&LG=en&DB=EPD)

)specify a 10x molar ratio of Diethylamine to Lysergic Acid, quite a large difference!
Is there any good solid reason to use such a large ratio of Diethylamine?
Other procedures, such as the "POCl3-Shulgin" method only use 5x amounts of Diethylamine.
Any comments? Thanks.
Title: OK... Can Someone at least post the reaction
Post by: Bubbleplate on September 21, 2004, 01:22:00 PM
Could someone lay out what occurs in the N,N-Carbonyl diimidazole procedure? I'm a cook, not a chemist! ;)
Title: Not sure if the CDI method is like the peptide
Post by: n00dle on September 21, 2004, 04:35:00 PM
Not sure if the CDI method is like the peptide coupling methods, but in peptide coupling methods only about 2 times excess amine to be reacted is utilized. The CDI overkill excess amine could possibly be to make sure that all of it reacts, as it's better to have leftover worthless amine rather than unreacted product, eh? (all methods have some ratio of over-excess amine, for this purpose, SWIM thinks.)
Title: CDI & DCC Coupling Mechanism
Post by: Rhodium on September 22, 2004, 05:30:00 AM


Source:

http://www.cem.msu.edu/~reusch/VirtualText4/special2.htm#top3 (http://www.cem.msu.edu/~reusch/VirtualText4/special2.htm#top3)



Title: Here's a Peptide Coupling Reagent Web Site
Post by: Bubbleplate on September 23, 2004, 03:36:00 AM
Good info and References:

http://www.albmolecular.com/features/tekreps/vol04/no01/ (http://www.albmolecular.com/features/tekreps/vol04/no01/)

Title: Another Question Regarding Solvent For Reaction
Post by: Bubbleplate on October 09, 2004, 02:28:00 PM
A few articles I've run across regarding Peptide Coupling Agents, (for instance

http://www.peptide-and-dna.com/marder.pdf (http://www.peptide-and-dna.com/marder.pdf)

)
it is suggested that Choloroform or DCM may be better solvents  to carry out the reaction in. The above article says "If the activation is carried out in a solvent of low dielectric constant such as CHCl3 or CH2Cl2, the formation of {the carbodiimide} occurs instaneously...... However, if the activation is carried out in a more Polar solvent such as DMF, no immediate reaction can be detected and a complex mixture..."
My question is, while the article is about Peptide coupling, would this also be applicable to the Lysergic Acid/N,N-Carbonyldiimidazole reaction?