Benzoxazole derivatives, process for their preparation and their use as optical brighteners
AssigneeHoechst Atiengesellschaft
InventorsUlrich Pintschovius, Erich Schinzel, Gunter Rosch
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Abstract
Compounds of the general formula I ##STR1## in which R represents hydrogen or a lower alkyl radical which may be further substituted, n is an integer of from 1 to 4, and which may contain further non-chromophoric substituents. They are prepared by reaction of the dichloride of naphthalene-1,4-dicarboxylic acid with an o-aminophenol and subsequent ring closure. These compounds can be used as optical brighteners.
Claims2
A compound of the formula ##STR27## wherein R is hydrogen, ethoxyethyl, methyl, ethyl, propyl or butyl and
- R.sub.1 is hydrogen or methyl.
A compound of the formula ##STR28## wherein R and R.sub.1 represent a lower alkyl radical which may be branched, or a hydrogen atom.
Dependencies are inferred from the claim text.