Process for preparing diphenyl ethers
AssigneeShell Internationale Research Maatschappij B.V.
InventorStuart P. Briggs
Life of this patent
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Abstract
Diphenyl ether derivatives of formula II ##STR1## wherein R.sub.1 represents a hydrogen or halogen atom or an alkyl or haloalkyl group, R.sub.2 and R.sub.3, which may be the same or different, each independently represents a hydrogen or halogen atom, or an alkyl, haloalkyl, nitro or cyano group, and R.sub.6 represents a hydrogen atom or an alkyl group, useful as intermediates in the preparation of diphenyl ether herbicides, are prepared by treating a compound of formula III ##STR2## where R.sub.1, R.sub.2 and R.sub.3 are as defined above with a dicarboxylic acid of formula R.sub.6 --CH(COOH).sub.2, where R.sub.6 is as defined above, in the presence of an organic base.
Claims9
A process for the preparation of a diphenyl ether derivative of Formula II ##STR6## wherein R.sub.1 represents a hydrogen or halogen atom or an alkyl or haloalkyl group, R.sub.2 and R.sub.3, which may be the same or different, each independently represents a hydrogen or halogen atom, or an alkyl, haloalkl, nitro or cyano group, and R.sub.6 represents a hydrogen atom or an alkyl group, said process comprising treating a compound of formula III ##STR7## where R.sub.1, R.sub.2 and R.sub.3 are as defined above with a dicarboxylic acid of formula R.sub.6 --CH(COOH).sub.2, where R.sub.6 is as defined above, in the presence of an organic base, to obtain a reaction mixture containing product of formula II as the major product, and separating the product of the formula II from the reaction mixture.
Dependencies are inferred from the claim text.