Boric acid Catalyzed Efficient Synthesis of Symmetrical N,N′-Alkylidene Bisamides

Symmetrical N,N'-alkylidene bisamides were synthesized in excellent yield by condensation of aromatic aldehydes and amides in the presence of boric acid as a catalyst under thermal and neat microwave irradiation conditions. It is the first successful report of boric acid has been used as Lewis acid catalyst for the preparation of symmetrical N,N'-alkylidene bisamides. The remarkable advantages offered by this method are green catalyst, mild reaction condition, simple procedure, fast reaction and moderate to good yield of products.