3067. 4′,5′-Dichlorofluorescein

Nomenclature

CAS number: 2320-96-9
4′,5′-Dichloro-3′,6′-dihydroxyspiro[isobenzofuran-1(3H),9′-[9H]xanthen]-3-one; D & C Orange no. 8; 4,5-dichloro-3,6-fluorandiol.
C20H10Cl2O5; mol wt 401.20.
C 59.87%, H 2.51%, Cl 17.67%, O 19.94%.

Description and references

Prepd by condensation of 2-chlororesorcinol with phthalic anhydride: Colour Index vol. 4 (3rd ed., 1971) p 4424.

Chemical structure

Properties

Orange powder, insol in water and in dil acids. Sol in alcohol and in dil alkali yielding solns which are orange with a greenish-yellow fluorescence. Slightly sol in glycerol and the glycols. Practically insol in oils, fats and waxes. If a soln of the dye in strong alkali is heated, a violet color is produced.

Derivative

Disodium salt.

Nomenclature

C.I. Solvent Orange 32; C.I. 45365.
C20H8Cl2Na2O5; mol wt 445.16.
C 53.96%, H 1.81%, Cl 15.93%, Na 10.33%, O 17.97%.

Note

Structure depicted as the open tautomer.