Process for the manufacture of bis-benzo-furanyl compounds
AssigneeHoechst Aktiengesellschaft
InventorErich Schinzel
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Abstract
Process for the manufacture of optically brightening bis-benzofuranyl compounds by cyclization of compounds of the formula ##STR1## in aprotic solvents and in the presence of alkali metal or alkaline earth metal carbonates.
Claims7
Process for the manufacture of bis[benzofuranyl-(2)] compounds of the formula (I) ##STR11## in which B denotes a direct link or one of the following groups ##STR12## P, Q, P' and Q, independent of one another, are hydrogen or halogen atoms, lower alkoxy or phenyl, optionally functionally modified carboxy groups, or P and Q as well as P' and Q' together denote a fused benzene nucleus, which comprises subjecting compounds of the formula II ##STR13## in which B, P, Q, P' and Q' are as defined above and R denotes alkyl, aryl or aralkyl and
- X stands for an anion,
- in an aprotic solvent and in the presence of an alkali metal or alkaline earth metal carbonate to a cyclization reaction.
Dependencies are inferred from the claim text.