Synthesis and 1H-NMR spectra of halogenated spiro[isobenzofuran-1(3H),9′(9H)-6′-(methylcyclohexylamino)-3′-methyl-2′-anilinoxanthene]-3-ones

Reaction of spiroisobenzofuran-1(3H).9′(9H)-6′-(methylcyclohexylamino)-3′-methyl-2′-anilinoxanthene]-3-one ( 1 ), which is typical leuco fluoran dye, with N-bromosuccinimide and N-chlorosuccinimide leads to halogenated derivatives 2a–2c and 3 , respectively. Their structures were established by two-dimensional proton-proton (COSY) experiment and their thermal properties examined by means of DSC and compared with commercially available 1 .