Tri-tert-butylphosphine tetrafluoroborate → HCID 57541263, compound

Participants

Reaction Conditions

Reaction Steps

Sodium tert-butoxide (8.99 g, 94 mmol) was added in one portion to a 250 mL flask containing methyl {[methyl(phenyl)amino]sulfonyl}acetate (7.59 g, 31.2 mmol) and dioxane (125 ml) at room temperature. After 15 min., 7-bromo-3-chloro-5H-benzo[4,5]cyclohepta[1,2-b]pyridin-5-one (10.00 g, 31.2 mmol) was added followed by palladium(II) acetate (0.350 g, 1.560 mmol) and tri-t-butylphosphonium tetrafluoroborate (1.358 g, 4.68 mmol). The resulting suspension was degassed by sparging with nitrogen for 30 min. Then, the mixture was heated to 90° C. in a pre-warmed bath and left to stir for 1 h. Then, the reaction mixture was cooled to room temperature, acidified with 1N HCl (100 mL), basified with saturated aqueous sodium hydrogen carbonate (400 mL) and extracted with dichloromethane (3×250 mL). The combined organics were dried over anhydrous Na2SO4, filtered and concentrated under reduced pressure. The residue was purified by column chromatography on silica gel (EtOAc/Hexanes gradient) to afford the title compound as a yellow foam. 1H NMR (600 MHz, DMSO-D6) δ 8.99 (d, 1H); 8.46 (d, 1H); 8.42 (d, 1H); 8.03 (dd, 1H); 7.81 (d, 1H); 7.44 (d, 1H); 7.33 (d, 1H); 7.22 (m, 2H); 7.17 (m, 2H); 7.11 (m, 1H); 6.10 (s, 1H); 3.71 (s, 3H); 3.20 (s, 3H). LRMS (APCI) calculated for C24H20ClN2O5S [M+H]+, 483.1; found 483.0.

Provenance & Evidence