Zeneca Limited

Avecia Limited

Fujifilm Imaging Colorants, Inc.

John Heathcote Atherton

Stephen Martin Brown

James Peter Muxworthy

Martin Lennon

Andrew John Blacker

Jan Michael Fielden

Ian Hodgkinson

David Martin Payne

Zachary Richard Meadows

David Anthony Jackson

Ian Jeffrey Priestley

Douglas John Edwin Spencer

David Dodman

A process for the preparation of a desired chemical compound in a continuous reactor in which a part of the product stream exits the reactor and part of the product stream is recycled around the reactor in order to reduce the amount of buffer that would otherwise be required.

Manufacturing process

A process for the preparation of a compound of formula (I): wherein Ar represents an optionally substituted aromatic carbocycle or heterocycle, and Rand Rindependently represent hydrogen, Calkyl, C(O)Calkyl or optionally substituted aryl provided that Rand Rare not both hydrogen which process comprises reacting together a compound of formula (II):Ar&#x2014;X&#x2003;&#x2003;(II)wherein Ar is as defined in relation to formula (I) and X represents a leaving group with a a compound of formula (III) wherein Rand Rare as defined in relation to formula (I) under aqueous conditions in the presence of a Pd (II) salt, a ligand and a Group I or Group II metal hydroxide base at a pH greater than 7. Compounds of formula (I) may be hydrolysed to the corresponding hydrazine.

Process for the preparation of aryl hydrazone and aryl hydrazine

A process for the preparation of a compound of general formula I: ##STR1## wherein: R.sup.1 is hydrogen or C.sub.1 -C.sub.6 alkyl, C.sub.2 -C.sub.6 alkenyl or C.sub.2 -C.sub.6 alkynyl, any of which may optionally be substituted with one or more substituents selected from halogen and OH; or COOR.sup.4, COR.sup.6, CONR.sup.4 R.sup.5 or CONHSO.sub.2 R.sup.4 ;

Process for the nitration of diphenylethers

A process for the nitration of an aromatic or heteroaromatic compound with a nitrating agent comprising nitric acid or a mixture of nitric and sulphuric acids, characterised in that nitration is performed in a solvent comprising at least 50% v/v of a C.sub.1 -C.sub.6 alkyl ester of a C.sub.1 -C.sub.4 carboxylic acid. The process is of particular use for the nitration of diphenyl ethers to give compounds which are useful as herbicides or as intermediates in the synthesis of herbicides.

Nitration process

A process whereby N-phosphonomethylglycine (glyphosate) or its salts is manufactured by: 1) forming N-phosphonomethylglycinonitrile by reacting aminomethylphosphonic acid, an alkali metal cyanide and formaldehyde in aqueous solution at a pH in the range from 10 to 13 (and preferably from 11 to 11.5) whilst adding mineral acid at a rate sufficient to maintain the pH within the desired range, and thereafter 2) hydrolysing the N-phosphonomethylglycinonitrile product of Stage (1) to form a salt of N-phosphonomethylglycine and optionally 3) neutralising the salt of N-phosphonomethylglycine to form N-phosphonomethylglycine

Process for the production of N-phosphonomethylalycine and salts thereof

Growing community of inventors

Huddersfield, United Kingdom

John Heathcote Atherton