Efficient Synthesis of New N-Benzyl- or N-(2-Furylmethyl)cinnamamides Promoted by the ‘Green’ Catalyst Boric Acid, and Their Spectral Analysis

Abstract

New N-benzyl- or N-(2-furylmethyl)cinnamamides were prepared in good to excellent yields by amidation reactions between cinnamic acid and benzylamines or (2-furylmethyl)amine in the presence of 5 mol% boric acid. All the cinnamamides were characterized by IR and ¹H and ¹³C NMR spectroscopy.

Key words

amides - amidation - catalysis - carboxylic acids - N-benzylamides

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22

The boric acid promoted azeotropic reflux procedure seems not to be limited to cinnamic acid or its derivatives; see refs. 11 and 13.

23

Compounds 3c, 3g, and 3j displayed antifungal activity, especially 3c, which showed to be a moderate antifungal agent for three different dermatophytic pathogenic fungi stumps. All the evaluated products (3a-j) possessed poor anti-AChE activity. These results will be published elsewhere.