Synthesis of Novel 4-FluorophenylSubstituted Carbocyclic and Heterocyclic Compounds

We demonstrated the first synthesis of 2-hydroxyimino-1-(4-fluorophenyl)butane-1,3-dione by nitrosation of 1-(4-fluorophenyl)butane-1,3-dione with sodium nitrite in acetic acid. The three- component reaction of 2-hydroxyamino-1-(4-fluorophenyl)butane-1,3-dione with acetone and aliphatic dialkylamines (diethylamine or diethanolamine) leads to new N, N-dialkyl-3-methyl-4-nitroso-5-(4-fluorophenyl) anilines. Cyclocondensation of 2-hydroxyimino-1-(4-fluorophenyl)butane-1,3-dione with hydrazine hydrate leads to 3-methyl-4-nitroso-5-(4-fluorophenyl)-1H-pyrazole. Reduction of nitrosopyrazole gives the corresponding fluoro- substituted aminopyrazole. The synthesized compounds were characterized by IR, NMR, UV-Vis, and MS.