Abstract
It has been found that a Mannich-type reaction catalyzed by an
intramolecular phenolic hydroxy group involves simply heating a
hydroxybenzaldehyde with a secondary amine and a dialkyl phosphite
in alcohol, produced highly substituted α-aminomethylphosphonates.
The corresponding reaction can hardly be detected if the hydoxy
group of the benzaldehyde is absent or blocked, or the hydroxybenzaldehyde
is replaced by 2′-hydroxyacetophenone.
Key words
Mannich-type reaction - autocatalysis - α-amino
phosphonates - secondary amine - hydroxybenzaldehyde
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