Microwave-Assisted, Solvent Free Preparation of 1,5-Benzodiazepine Derivatives Using Nanomagnetic-Supported Sulfonic Acid as a Recyclable and Heterogeneous Catalyst

Abstract

A new preparation of 1,5-benzodiazepine derivatives has been achieved in good to excellent yields by the condensation of o-phenylenediamine with a variety of ketones employing nano-γ-Fe 2 O 3 -SO 3 H as catalyst under microwave irradiation and solvent-free conditions. Recyclable nano-γ-Fe 2 O 3 -SO 3 H provided high reactivity and was easily separated from the reaction mixture by using an external magnet. The advantages offered by this method are based on the principles of 'green chemistry': a facile and rapid reaction, no solvent, easy separation of products and good to excellent yields..

o-Phenylenediamine as a Source of Fused Azole, Azine, and Diazepine Derivatives

“…Consequently, the development of new strategies for the synthesis of fused heterocyclic systems is of prime importance. In the present study, the reaction of binucleophilic nitrogen system like o-phenylenediamine (1) with commercially available reagents was explored to build up seven-, six-, and five-membered heterocyclic systems [6][7][8][9][10][11][12][13][14][15][16][17].…”

The role of hollow magnetic nanoparticles in drug delivery

“…1,2 Nowadays, they are applied in many elds such as bioimaging and sensing; on a smaller scale, they are used as catalysts and in medicine. [3][4][5][6][7][8][9][10][11][12][13] Hence, the enormous interest in the efficiency of these materials can be easily understood. Specically, Frey and co-workers carefully reviewed the synthesis and applications of MNPs in drug delivery.…”

An Easy and Efficient Method for the Synthesis of Quinoxalines Using Recyclable and Heterogeneous Nanomagnetic‐Supported Acid Catalyst under Solvent‐Free Condition

“…Many of the methods reported above have certain drawbacks such as use of expensive and moisture sensitive reagents, non‐reusable catalyst, laborious and complex work‐up procedure, undesirable side products and unsatisfactory yields. During the course of our recent investigation towards the synthesis of bio‐active heterocycles, we discovered an efficient and reusable nanomagnetic‐supported sulfonic acid catalyst (nano‐√‐Fe 2 O 3 ‐SO 3 H) for the synthesis of various heterocycles such as 1,5‐benzodiazepines, 1,4‐dihydropyridines, and α,α′‐bis(substituted‐benzylidine)cycloalkanones . The catalyst is also used in certain familiar named reactions such as the Hantzsch reaction for the synthesis of polyhydroquinolines and in the Biginelli reaction for the synthesis of 3,4‐dihydropyrimidin‐2 H ‐ones .…”