Synthesis and Characterization of New Pyrazoline and Isoxazoline Derivatives Based on Fluorene


The aim of the present work is a synthesis of new fluorene derivatives containing heterocyclic moieties. These compounds were synthesized in four groups, each group containing five compounds. The first group was made up of 2-(3-aryl-2-propenoyl) fluorene derivatives (1a-e) synthesized from the reaction of 2-acetyl fluorene with appropriate aromatic aldehyde in the presence of sodium hydroxide. The other three groups involved compounds produced from the reaction of (1a-e) with hydrazine hydrate (99%) in presence of acetic acid (96%) to give 1-acetyl-5-aryl-3-(fluoren-2-yl) pyrazoline derivatives (2a-e), and with phenyl hydrazine in presence of piperidine to produce 1-phenyl-5-aryl-3-(fluoren-2-yl) pyrazoline derivatives (3a-e), and with hydroxylamine hydrochloride in presence of pyridine to obtain the 5-aryl-3-(fluoren-2-yl) oxazoline derivatives (4a-e). All the compounds of the above three groups were substituted at position (5) in pyrazoline and isoxazoline ring with different aryl groups according to aromatic aldehyde used in the preparation of the first group series compounds. The synthesized compounds were identified by spectroscopic methods: FT-IR and 1H-NMR.