Process for the production of 3-substituted 7-amino-coumarins
Abstract
Abstract Process for the production of 3-substituted 7-amino-coumarins of the general formula IN WHICH X stands for hydrogen or a substituent; n denotes the numbers 1 to 3; and R1 denotes an optionally substituted phenyl or napthyl group, an aromatic-heterocyclic radial which is attached via a C-C bond, on a carboxyl group, characterized in that substituted Beta -phenyl-acrylic acid nitriles of the general formula IN WHICH R1, X and n have the same meaning as above; and R2 stands for a radical WHERE R3 and R4 denote an alkyl radical, for a radical -SO3Z where Z denotes H or a metal atom, or for a radical -CH2OR5where R5 denotes an alkyl, aralkyl, or aryl radical, are heated in an aqueous-acidic medium, optionally in the presence of a water miscible or water-immiscible organic solvent, at temperatures of about 80*-200* C.
Inventors
- 👤 Hans Knupfer
- 👤 Carl-Wolfgang Schellhammer
Bibliographic Details
Claims Analysis
Total Claims: 4References Cited (Backward Citations)
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