N,N-diethyl indole-3-acetamide

[Zamboni]

N,N-diethyl indole-3-acetamide

In this post

Post 272175

(Ritter: "Re: Indole Grignards", Tryptamine Chemistry)
Ritter says:

   
Diethylamine practically won't even react with the methyl ester, even when refluxed for 24 hours!

In Archiv der Pharmazie volume 275 pages 506-516 (1937) its gives a process for making indoleacetamide from ethyl indole-3-acetate and what seems to be strong ammonia solution.  Its written in German.  When diethylamine was substituted for ammonia there was no reaction even when tried at 200 degrees using a bomb tube.
  Dimethylamine reacts.  Why is there this difference with diethylamine?
See

https://www.thevespiary.org/rhodium/Rhodium/chemistry/indoleaceticacid.html