Triethylamine → 5,5'-(1,2-Ethynediyl)bis-(1,3-Isobenzofurandione)

Participants

Reaction Conditions

Reaction Steps

4-Bromophthalic anhydride (21.8 g), dimethylacetamide (66 ml) and triethyl amine (16 ml) were mixed and purged with nitrogen. Thereafter, triphenylphosphine (113 mg), bis(triphenylphosphine)palladium(II) dichloride (101 mg) and copper iodide (55 mg) were added. The resulting mixture was pressurized with acetylene (approximative 2 bar) and heated to 80° C. Once the 4-bromophthalic anhydride had been consumed, which was determined by HPLC subsequent to methanolysis, acetic acid (87 ml) was added and the resulting mixture was cooled to 40° C. Mixture was filtered, and resulting solid washed twice with 10 ml acetic acid. The resulting product was dried at <100 mbar at 110° C., providing 7.8 g 5,5′-(ethyne-1,2-diyl)bis(isobenzofuran-1,3-dione) in a yield of 51%. The bromide content of the final product was determined to be 150 ppm by ion chromatography.

Provenance & Evidence