Pyranine → 8-(5-Carboxypentoxy)pyrene-1,3,6-trisulfonic acid

Participants

Reaction Steps

A mixture of 8-hydroxypyrene-1,3,6-trisulfonate sodium salt (2.6 g), diisopropylethylamine (2 g) and ethyl 6-bromohexanoate (7 g) in methanol (150 mL) was refluxed for 24 hours. The solvent was removed by rotary evaporation. The product was purified by HPLC. The isolated ethyl ester was redissolved in methanol (100 mL). About 0.5 g NaOH dissolved in 25 mL water was added. The resulting solution was stirred overnight. The methanol was removed by rotary evaporation. To the remaining aqueous solution was added acid until the solution became acidic. The precipitate was collected by filtration and dried under vacuum to give 8-(5-carboxypentoxy)pyrene-1,3,6-trisulfonic acid.

Provenance & Evidence