Synthesis and characterization of bromoquinazolinone substituted spiro[isobenzofuran-1,9′-xanthene]-3-ones

Some new bromoquinazolinone substituted fluoran compounds were synthesized by the reaction of the keto acid, 2-(4-diethylamino-2-hydroxybenzoyl)benzoic acid with different 3-(3/4-hydroxyphenyl)-2-methyl/phenylbromo-4(3H) quinazolinones in the presence of a dehydration condensing agent like sulfuric acid. Various quinazolinones were prepared by reacting different monobromo/dibromobenzoxazine-4-ones with 3-aminophenol or 4-aminophenol in the presence of pyridine as a solvent. All the synthesized fluoran compounds were identified by conventional methods such as melting point, IR, ¹H NMR, ¹³C NMR, elemental analysis and UV-visible spectroscopy in organic solvents and 95% acetic acid. All these colorless fluorans develop a color in contact with electron accepting compounds.