3,4-dibromo-5H-furan-2-one

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of 3,4-dibromofuran-2(5H)-one (1 g, 0.004 mol) in DMF (10 mL) was added Cs2CO3 (1.34 g, 0.004 mol) followed by morpholine (360 mg, 0.004 mol) at room temperature under a N2 atmosphere. The reaction mixture was then stirred for 30 minutes, quenched with ice water and extracted with EtOAc (2×50 mL). The combined organic layers were washed with water, dried over anhydrous Na2SO4, filtered, and concentrated in vacuo to afford 3-bromo-4-morpholinofuran-2(5H)-one (0.87 g, 85%) as a solid. quenched with ice water extracted with EtOAc (2×50 mL) The combined organic layers were washed with water dried over anhydrous Na2SO4 filtered concentrated in vacuo

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of 3,4-dibromofuran-2(5H)-one (1 g, 0.004 mol) in DMF (10 mL) was added Cs2CO3 (1.34 g, 0.004 mol) followed by morpholine (360 mg, 0.004 mol) at room temperature under a N2 atmosphere. The reaction mixture was then stirred for 30 minutes, quenched with ice water and extracted with EtOAc (2×50 mL). The combined organic layers were washed with water, dried over anhydrous Na2SO4, filtered, and concentrated in vacuo to afford 3-bromo-4-morpholinofuran-2(5H)-one (0.87 g, 85%) as a solid. quenched with ice water extracted with EtOAc (2×50 mL) The combined organic layers were washed with water dried over anhydrous Na2SO4 filtered concentrated in vacuo

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture containing 3,4-dibromofuran-2(5H)-one (0.518 g, 2.142 mmol), 4-trifluoromethylphenylboronic acid (0.509 g, 2.680 mmol), trans-dichlorobis(triphenylphosphine)palladium (II) (0.069 g, 9.831×10−2 mmol), tetrabutylammonium iodide (0.038 g, 1.029×10−1 mmol) and cesium fluoride (0.872 g, 5.740 mmol) in toluene (10 mL) and water (10 mL) was stirred at room temperature for 72 h under nitrogen. Brine (50 mL) was added and the product extracted with ethyl acetate (3×50 mL). The organic fractions were combined, washed with brine (3×50 mL), dried over anhydrous magnesium sulfate and evaporated to dryness under reduced pressure to give an orange solid. The resulting solid was chromatographed (silica gel: eluent 25:75 dichloromethane/light petroleum) to give 3-bromo-4-(4′-(trifluoromethyl)phenyl)furan-2-(5H)-one 16 (0.312 g, 47%) as a pale yellow powder. Further purification by recrystallisation from dichloromethane/light petroleum furnished colourless needles, (ref. PDS-2-115); 1H NMR (CDCl3, 300 MHz) δ 7.94 (d, 2H, J=8.3 Hz, H3′, H5′), 7.78 (d, 2H, J=8.3 Hz, H2′, H6′), 5.21 (s, 2H, H5). the product extracted with ethyl acetate (3×50 mL) washed with brine (3×50 mL) dried over anhydrous magnesium sulfate evaporated to dryness under reduced pressure to give an orange solid The resulting solid was chromatographed (silica gel: eluent 25:75 dichloromethane/light petroleum)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of 3,4-dibromofuran-2(5H)-one (1 g, 0.004 mol) in DMF (10 mL) was added Cs2CO3 (1.34 g, 0.004 mol) followed by morpholine (360 mg, 0.004 mol) at room temperature under a N2 atmosphere. The reaction mixture was then stirred for 30 minutes, quenched with ice water and extracted with EtOAc (2×50 mL). The combined organic layers were washed with water, dried over anhydrous Na2SO4, filtered, and concentrated in vacuo to afford 3-bromo-4-morpholinofuran-2(5H)-one (0.87 g, 85%) as a solid. quenched with ice water extracted with EtOAc (2×50 mL) The combined organic layers were washed with water dried over anhydrous Na2SO4 filtered concentrated in vacuo