Process for preparation of o-(2,6-dichloroanilino)phenylacetic acid and novel intermediate for use in preparation of the same
AssigneeIkeda Mohando Co., Ltd.
InventorFujio Nohara
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Abstract
Disclosed is a process for the preparation of o-(2,6-dichloroanilino)phenylacetic acid (Diclofenac) or its pharmacologically acceptable acid addition salt, which comprises hydrolyzing an N,N-disubstituted-o-(2,6-dichloroanilino)phenylacetamide derivative with an alkali. Also a novel intermediate for use in the preparation of Diclofenac, that is, an N,N-disubstituted-o-halogenophenylacetamide in which the halogen is iodine or bromine, is disclosed.
Claims2
A process for the preparation of o-(2,6-dichloroanilino)phenylacetic acid or its pharmacologically acceptable acid addition salt, which comprises reacting an N,N-disubstituted-o-halogenophenylacetamide derivative represented by the following general formula (I):
- ##STR31## wherein R.sub.1 and R.sub.2, which may be the same or different, stand for a lower alkyl group, or one of R.sub.1 and R.sub.2 stands for a lower alkyl group and the other of R.sub.1 and R.sub.2 stands for a phenyl or benzyl group, or R.sub.1 and R.sub.2 are bonded together to form a heterocyclic ring together with a nitrogen atom and/or an oxygen atom, and X stands for an iodine or bromine atom,
- with 2,6-dichloroaniline in the presence of a copper catalyst to form an N,N-disubstituted-o-(2,6-dichloroanilino)phenylacetamide represented by the following general formula (II):
- ##STR32## wherein R.sub.1 and R.sub.2 are as defined above, and hydrolyzing with an alkali.
A process for the preparation of N,N-disubstituted-o-(2,6-dichloroanilino)phenylacetamide derivatives represented by the following general formula (II):
- ##STR33## wherein R.sub.1 and R.sub.2, which may be the same or different, stand for a lower alkyl group, or one of R.sub.1 and R.sub.2 stands for a lower alkyl group and the other of R.sub.1 and R.sub.2 stands for a phenyl or benzyl group, or R.sub.1 and R.sub.2 are bonded together to form a heterocyclic ring together with a nitrogen atom and/or an oxygen atom,
- which comprises reacting an N,N-diisubstituted-o-halogenophenylacetamide derivative represented by the following general formula (I):
- ##STR34## wherein R.sub.1 and R.sub.2 are as defined above, and X stands for an iodine or bromine atom, with 2,6-dichloroanline in the presence of a copper catalyst.
Dependencies are inferred from the claim text.