An improved process for the synthesis of 4,4- Diamino Diphenyl Methane and its substituted derivatives

Rugmini Sukumar, Kuzhunellil Raghavan Pillai Sabu, Malathy Lalithambika, Damodaran Bahulayan

The present invention provides an improved process for the synthesis of 4,4″- diaminodiphenymlethane and its substituted derivatives which comprises adding aromatic amino compound to a mixture of eco-friendly catalysts such as natural clays and kaolins and water in a ratio ranging from 1:100 to 1:500 followed by addition of formaldehyde and continuing the stirring for a period in the range of 0.5 to 1.0 h, and separating the residue obtained from step (i) from the reaction mixture by known methods and purifying by conventional techniques. The process is simple, speedy, selective and eco-friendly with 100% conversion.