Potassium Carbonate → tert-butyl 3-bromo-7-(2-fluoropyridin-3-yl)-5'H-spiro[chromeno[2,3-b]pyridine-5,4'-thiazole]-2'-ylcarbamate

Participants

Reaction Conditions

Reaction Steps

A vial was charged with tert-butyl 3-bromo-7-iodo-5′H-spiro[chromeno[2,3-b]pyridine-5,4′-thiazole]-2′-ylcarbamate (0.454 g, 0.791 mmol), 2-fluoropyridin-3-ylboronic acid (0.167 g, 1.186 mmol), potassium carbonate (0.546 g, 3.95 mmol), and tetrakis(triphenylphosphine)palladium(0) (0.091 g, 0.079 mmol). The vial was flushed with Ar (g), then dioxane (5.27 mL) and water (2.64 mL) were added in sequence. The vial was sealed and heated at 80° C. for one hour. The reaction was diluted with EtOAc and washed with water. The aqueous layer was extracted with EtOAc, and the combined organic layers were dried with sodium sulfate, filtered, and concentrated. The material was purified via silica gel chromatography (gradient elution 0-50% EtOAc:Hex) to afford tert-butyl 3-bromo-7-(2-fluoropyridin-3-yl)-5′H-spiro[chromeno[2,3-b]pyridine-5,4′-thiazole]-2′-ylcarbamate as a light yellow solid. MS m/z=545.1. Calc'd for C24H20BrFN4O3S: 543.41.

Provenance & Evidence