Design and Synthesis of Acidic Deep Eutectic Solvents Based on Choline Chloride and Discovery of a Highly Efficient Catalyst for the Synthesis of Benzoazepinones

Benzodiazepines are biaryl lactams which have attracted the attention of scientist as these arethe privileged core, discovered in many alkaloids and pharmaceutically relevant organic molecules.This moiety is also very important due to being a core intermediate for LY411575, anγ-secretase inhibitor, a clinical candidate for Alzheimer’s disease [1].They are antiinflammatory,antidepressive, anticonvulsant, antiviral, antimicrobial, anti-HIV, antianxiety,anti-ulcerative, antitumor, analgesic, antihistaminic, anti-allergic, hypnotic and antipyretic [2].Benzodiazepines are generally synthesized by the reaction of β-haloketones with ophenylenediamine,condensation of α,β-unsaturated compounds with o-phenylenediaminesand condensation of ketones with o-phenylenediamine in the presence of ytterbium trichloride.The disadvantages of previously reported procedures for the synthesis of benzodiazepinesare their multistep reactions, anhydrous conditions, tedious work-up, long reactiontimes and generation of undesirable by-products [3].Herein, we report the acidic deep eutectic solvents based on choline chloride which can beused as an effective catalyst for the synthesis of benzoazepinones derivatives by the condensationof o-phenylenediamines, dimedone and various benzaldehydes derivative.