Ag₃PW₁₂O₄₀: A Novel and Recyclable Heteropoly Acid for the Synthesis of 1,5-Benzodiazepines under Solvent-Free Conditions

Abstract

o-Phenylenediamines undergo smooth condensation with ketones having hydrogens at α-position on the surface of heteropoly acid (Ag₃PW₁₂O₄₀) under extremely mild conditions to afford the corresponding 1,5-benzodiazepines in excellent yields with high selectivity. The catalyst can be recovered by simple filteration and can be reused in subsequent reactions.

Keywords

heteropoly acids - o-phenylenediamines - ketones - benzodiazepines

References and Notes

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