Abstract: A process for direct fluorination of etherified or unetherified hydroxy group-bearing aromatic compounds, which comprises reacting an etherified or unetherified hydroxy group-bearing aromatic compound with fluorine gas to give the corresponding etherified or unetherified hydroxy group and at least one fluorine atom-bearing aromatic compound.

Abstract: A process for preparing a trifluoromethylbenzonitrile derivative of the formula: ##STR1## wherein X is hydrogen, lower alkyl, halogenated lower alkyl, lower alkoxy, nitro, hydroxyl, amino, cyano, carboxyl or sulfon which comprises reacting trifluoromethylhalogenobenzene of the formula: ##STR2## wherein X is as defined above, and Y is halogen with copper (I) cyanide in a solvent selected from the group consisting of hexamethylphosphoric triamide, N-methylpyrrolidone and a mixture thereof in the presence of a catalyst selected from the group consisting of (A) bromine, (B) iodine, (C) a combination of bromine or iodine and metallic copper and (D) copper (II) bromide, by which process the compound (I) is prepared in a good yield, and by-products are produced in a lower yield than the conventional processes.

Abstract: A process for production of 5-fluorouracil and its derivatives which comprises reacting a cytosine compound of the formula: ##STR1## wherein R is a hydrogen atom or a saccharide residue with fluorine or fluorine fluorosulfonate (FOSO.sub.2 F) in an aqueous medium to give the corresponding 5-fluorouracil compound of the formula: ##STR2## wherein R is as defined above.