Council of Scientific and Industrial Research

Central Salt and Marine Chemicals Research Institute

Gadde Ramachandraiah

Pushpito Kumar Ghosh

Maheshkumar Ramniklal Gandhi

Jatin Rameshchandra Chunawala

Pratyush Maiti

Rahul Jasvantrai Sanghavi

Sumesh Chandra Upadhyay

Satish Hariray Mehta

Sanjay Shambhubhai Vaghela

Ashutosh Vasant Bedekar

Subbarayappa Adimurthy

Venkata Rama Krishna Sarma Susarla

Kumar Pushpito Ghosh

Aditya Shantilal Mehta

Sudhindra Nath Misra

Ashok Dahyabhai Jethva

Rajesh Popatlal Pandya

Subbarayyappa Adimurthy

Mallampati Subbareddy

Rajendra Patil

Girdhar Joshi

Harshad Brahmbhatt

Manoj Kunjabihari Agrawal

Paresh Ukabhai Patoliya

Mrinal Vinodbhai Sheth

A highly pure 3,5-dibromo-4-hydroxybenzonitrile (bromoxynil) has been prepared in high yield from 4-hydroxybenzonitrile using eco-friendly brominating reagent comprising of 2:1 mole ratio of bromide to bromate salts in aqueous acidic medium without any catalyst under ambient conditions with no work up procedure. The product 3,5-dibromo-4-hydroxybenzonitrile was obtained in 91-99% yield with melting point 189-191&#xb0; C. and more than 99% purity by gas chromatographic analysis without any purification.

Process for the eco-friendly preparation of 3, 5-dibromo-4-hydroxybenzonitrile

A new eco-friendly process is described in the present invention for the preparation of bromobenzene through substitution of one of the C&#x2014;H proton of benzene ring with a highly reactive hypobromous acid generated in situ, said process comprises the steps of activating a water soluble, easy to handle, brominating reagent with a mineral acid at elevated temperature and atmospheric pressure to generate active bromine species which in turn reacts with benzene.

Process for eco-friendly synthesis of bromobenzene

The present invention relates to a process for electrochemical oxidation of bromide to bromine, more particularly to oxidation of bromide ions in brine, bittern and effluents using an indigenous cation exchange membrane flow cell.

Process for electrochemical oxidation of bromide to bromine

A highly pure and colorless tetrabromobisphenol-A (TBBPA) possessing melting point in the range of 178-182&deg; C. is prepared in yields of 50-70% in first batch and 90-100% when the spent organic layer is recycled. In this method, the corrosive liquid bromine is displaced by sodium bromide/hydrobromic acid as brominating agent. Further, sodium bromate is used as an oxidizing as well as brominating agent to utilize the hydrobromic acid that is produced during the bromination of bisphenol-A (BPA). The reaction is conducted at 10-15&deg; C. in a mixture of methylene chloride-water or carbon tetrachloride-water in the presence of hydrochloric acid and sodium lauryl sulfate. The crystalline product settled at the bottom of the reaction vessel is filtered, washed, dried and weighed. The spent organic layer is recycled in subsequent batches to maximize the overall yield of product recovered directly as solid and to minimize generation of organic effluent.

Eco-friendly method of preparation of high purity tetrabromobisphenol-A

Growing community of inventors

Bhavnagar, India

Gadde Ramachandraiah