Brominated and iodinated thiofluoresceins
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Conditions were found for the synthesis of mono-, di-, tri-, and tetrabromo- and -iodo-substituted thiofluoresceins. Iodination and bromination of thiofluorescein with molecular iodine and bromine in 1 N aqueous sodium hydroxide gave mixtures of the corresponding 2,4,5,7-tetra- and 2,4,5-trihalo derivatives in 71/14 (Y = I) and 73/13% yield (Y = Br), respectively. In the reactions of thiofluorescein with bromine in acetic acid and with iodine in methanol at a substrate-to-halogen ratio of 1 : 2, 4,5-dibromo- and 4,5-diiodothiofluoresceins were isolated in 56 and 67% yield. Analogous reactions with equimolar amounts of the reactants produced 59% of 4-bromothiofluorescein and 51% of 4-iodothiofluorescein.
KeywordsElectronic Absorption Spectrum Aqueous Sodium Hydroxide Molecular Iodine Lactone Form Thioxanthen
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- 2.El’tsov, A.V., Ponyaev, A.I., and Martynova, V.P., Zh. Obshch. Khim., 1992, vol. 62, p. 1626.Google Scholar
- 3.German Patent no. 636 224, 1936; Chem. Abstr., 1937, vol. 31, p. 872.Google Scholar
- 4.Apostolova, E.S. and El’tsov, A.V., Zh. Obshch. Khim., 1990, vol. 60, p. 2606.Google Scholar
- 7.Lissitzky, S., Vigne, J., Ruby, Ph., and Fondarai, J., Bull. Soc. Chim. Fr., 1959, p. 389.Google Scholar