Two methods for the preparation of 3-dialkylaminomethyl derivatives (Mannich bases) of 4-aminocoumarin: A new type of intramolecular hydride transfer

Article abstract of DOI:10.1055/s-1995-3971

The transformation of 4-alkylaminocoumarin-3-carbaldehydes (1b-f) by treatment with secondary amines 2a-i into 3-dialkylaminomethyl-4-aminocoumarins 4a-i via intramolecular hydride transfer is reported. The structure of 4 was ascertained by independent Mannich reaction of 4-aminocoumarin (5) yielding the 3-dialkylaminomethyl derivatives 4a-e. By treatment of 1e with primary amine 6 only the usual Schiff base 7 was obtained.