Carbon Dioxide → 2,5-Thiophenedicarboxylic acid

Participants

Reaction Conditions

Reaction Steps

The di-silver of thiophene-2.5-dicarboxylic acid was prepared in 96 mole % yield by reacting 34.4 grams, 0.2 moles, of disodium thiophene-2,5-dicarboxylate in 500 milliliters of water with 0.4 moles of silver nitrate in 500 milliliters of water, collecting the precipitated silver salt on a filter, followed by washing and drying of the salt. The di-silver salt, 7.75 grams, and 0.02 moles, which decomposes at 315° C, was placed as a thin layer of powdered silver salt along the length of a Vycor reactor tube and heated in a furnace under nitrogen at 350° C for two minutes. Carbon dioxide (CO2) evolved with a sudden puffing up. Combustion of the silver salt subsided with the formation of the polymer and with cessation of evolution of CO2. Heating was stopped and the nitrogen purge was maintained while the tube and contents cooled to room temperature. The calculated loss of CO2 for 0.04 moles CO2 was 1.76 grams. Actual weight loss was 1.95 grams. The resulting carbon-like polymer containing silver analyzed: carbon 15.4%, hydrogen 0.6%, sulfur 4.4%, and silver 79.7%.

Provenance & Evidence