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Tetra-alkyl-ammonium Hydroxide Alkaloid Hydrolysis


Standard procedure calls for alkaline hydrolysis of Lysergic Acid amides (ergotamine, LSA, etc.) with a Methanolic solution of Potassium hydroxide to obtain Lysergic Acid.
However, Patent US6242603 describes a method of preparing Lysergic Acid by isomerizing Paspalic Acid with a Tetra-alkylammonium hydroxide solution, such as Tetra-butylammonium hydroxide, with excellent yields (80%).

My question is, couldn't a Tetra-alkyl-ammonium Hydroxide also be used in the alkaline hydrolysis of lysergic amides in place of Potassium hydroxide, and with better yields?

This question though 12 years old seems like it would still be of interest to some members. 

I really don't understand the mechanism of this reaction so I can't really comment on why it wouldn't or would work for the amide hydrolysis. 

It is apparently a fairly strong base, which seems a bit counter intuitive to me.  Is it actually strong enough induce amide hydrolysis?

I wonder if something could be done with the readily available choline? Choline hydroxide seems to have similar uses and is also considered a strong base.

The patent describes an isomerisation and the other reactions are a hydrolysis. So thats a different shoe to wear.

But strong base being strong base and as this good candidates for catalyzing a hydrolysis I had a look and it seems no. Won't work well.
Adding some KOH or NaOH though could change the picture.

Or LiOH alone or in combination with anything named above.
I have no idea why but LiOH seems just right to me.
A shot in the dark, nothing else.



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