Solvent‐Free Single‐Pot Mannich Reaction and Detoxification of Industrial Hazardous Waste Methyl Mercaptan Gas

Abstract

Environment pollution is causing serious human health issues and forest deterioration. Methyl mercaptan is a malodorous gaseous pollutant, which is a by product of sewage treatment plants, pulp plants, petrochemical plants, agrochemicals, and some pharmaceutical products. A long term exposure to methyl mercaptan may lead to adverse effects on central nervous system and cardiovascular system. The pharmaceutical industries are devoting significant efforts to develop process by using green solvents like water, and develop solvent‐free reactions. This will help to develop green, sustainable methods for the synthesis of API and reduce the manufacturing cost. A ZnCl2 catalyzed solvent‐free, one‐pot process for the synthesis of ranitidine and quenching of hazardous waste methyl mercaptan gas to a useful product have been developed.

A copper(ii) bromide/NMO system for α-amination of esters under continuous-flow conditions with reduced catalyst loading

“…15–19 Our lab is focussing on the development of green synthetic methods and their applications for the preparation of active pharmaceutical ingredients (APIs). 20,21…”

“…29 We attempted to study the α-amination of esters using a CuBr 2 catalyst, as part of our lab's current ongoing research on the development of Cu-catalysed synthetic methods and synthesis of APIs. 20,21 Herein, we report α-amination of esters under continuous-flow conditions with reduced CuBr 2 catalyst loading (0.05%) in the presence of NMO as a pharmaceutically acceptable oxidant. 26,30…”

Copper (II) bromide/NMO system for α-amination of esters in solvent-free condition

“…9 We attempted to study the amination of esters by using CuBr2 in a solvent-free condition, as part of our lab green chemistry approach for synthesis of pharmaceuticals. 20,21 Herein, we report wide substrate scope studies of α-amination of esters using CuBr2 as a catalyst in presence NMO as a pharmaceutically acceptable oxidant, 26,27 in a solvent-free condition.…”

“…20 We have developed a solvent-free Mannich reaction for preparation of ranitidine, used for treatment of stomach ulcer and acid reflux. 21 Copper is available in plenteous amount in nature, 22,23 and has been applied for several organic transformations, preparation of pharmaceuticals. 24 King and Ostrum described αbromination of ketones by using stochiometric amount of CuBr2.…”