Potassium Carbonate → HCID 58238626, compound

Participants

Reaction Steps

Potassium carbonate (1.6 g, 11.5 mmol, 3.0 equiv) was dissolved in water (15 mL) and added to compound 8A (1.0 g, 3.9 mmol, 1.0 equiv) and boronic acid 11 (2.0 g, 5.4 mmol, 1.4 equiv) in dioxane (30 mL). A stream of nitrogen was bubbled through the solution for 15 min and tetrakis(triphenylphosphine)palladium(0) (0.02 g, 0.02 mmol, 0.005 equiv) was added to the reaction. The reaction was refluxed for 4 hr at which point LC/MS and TLC indicated the reaction not to be complete. More of the boronate (0.7 g, 1.95 mmol, 0.5 equiv) and the palladium reagent (0.02 g) were added and refluxing was continued for 4 hr. The reaction was allowed to cool to room temperature, diluted with ethyl acetate (50 mL) and the organic layer separated and washed with saturated brine (50 mL). The organic layer was dried over sodium sulfate and absorbed onto silica gel (5 g) by concentration under reduced pressure. This material was purified on a silica gel column (45 g) by eluting with heptanes ethyl acetate (1%) in heptanes (300 mL) and ethyl acetate (3%) in heptanes (500 mL). The desired product was isolated in 80% yield (1.0 g).

Provenance & Evidence