Dimethylformamide → HCID 86657437, compound

Participants

Reaction Conditions

Reaction Steps

Inside a glove box, a 250 mL round-bottom flask equipped with a stirring bar, reflux condenser, and a septum was charged with N-trifluoromethanesulfonyl-2,5-dibromo-benzene-sulfonamide, sodium salt (19.45 g, 50 mmoles), activated copper powder (40 g), and DMF (80 mL). The flask was heated to 120° C. under nitrogen and stirred overnight. The solution was cooled to room temperature, filtered, and the solids washed with DMF. The solvent was evaporated by distilling under high vacuum and the resulting solids were dried under vacuum. The dark solids were dissolved in water by heating to a reflux and adding hydrochloric acid to give pH of 1. Residual dark solids were filtered off then the solution was neutralized using aqueous sodium hydroxide, which gave a yellow-brown precipitate that was removed by filtration. The mixture was saturated with sodium chloride and concentrated at reflux to 400 mL. Upon cooling, magenta solids precipitated from solution. The solids were collected by vacuum filtration and dried under vacuum to give 13.2 g (68% crude yield). The solids were dissolved in methanol at a reflux, treated with decolorizing carbon, filtered, evaporated, and dried in a vacuum oven at 150° C. under nitrogen purge. The solids were recrystallized from dioxane (50 mL) inside the glove box after filtering off residual solids. The crystals were collected and washed with dioxane to remove much of the remaining magenta color. The recrystallization was repeated inside the glove box to give colorless crystals, which were dried in a vacuum oven at 150° C. under nitrogen purge and transferred to a glove box for storage and handling to give 10.78 g (55% yield) of N,N′-bis(trifluoromethanesulfonyl)-4,4′-dibromo-biphenyl-2,2′-disulfonamide, disodium salt. 19F NMR (DMSO-d6): −78.31 (s).

Provenance & Evidence