Reaction Steps
(4S,5R)-4-(3-(trifluoromethyl)phenyl)-5-((tetrahydro-2H-pyran-2-yloxy)methyl)-oxazolidin-2-one (prepared as in Example 64, Steps A and B) (54 mg, 0.16 mmol) was added to a 10 mL reaction vessel with a screw cap and charged with acetonitrile (0.5 mL), 2-(4-chlorophenoxy)-5-bromopyrazine (47 mg, 0.16 mmol), copper (I) iodide (14 mg, 0.074 mmol), N,N′-dimethylethylenediamine (0.014 mL, 0.15 mmol), and potassium carbonate (44 mg, 0.32 mmol). The vessel was sealed, evacuated and back-filled with nitrogen twice, and then heated to 110° C. in a microwave for 30 min. The reaction mixture was cooled to room temperature, quenched with 1 M HCl, and extracted with ethyl acetate. The organic layer was dried, filtered and concentrated to give the crude intermediate which was immediately dissolved in methanol (5 mL) and treated with excess toluenesulfonic acid for 1 h. The reaction was quenched with 1 mL triethylamine, then concentrated to dryness and purified on silica gel (30% ethyl acetate/hexanes) to give the title compound as a white solid. 1H NMR (acetone-d6) 600 MHz δ (ppm) 8.91 (d, J=1.3 Hz, 1H), 8.05 (d, 1.3 Hz, 1H), 7.83 (s, 1H), 7.76 (d, J=7.6 Hz, 1H), 7.67 (d, J=7.8 Hz, 1H), 7.63 (t, J=7.7 Hz, 1H), 7.43 (d, J=8.8 Hz, 2H), 7.18 (d, J=8.8 Hz, 2H), 5.86 (d, J=5.0 Hz, 1H), 4.61 (ddd, J=5.4, 3.5, 3.0, 1H), 4.58 (t, J=5.7 Hz, 1H), 4.02 (ddd, J=12.4, 5.5, 3.5 z, 1H), 3.94 (ddd, J=12.3, 5.9, 3.5 Hz, 1H); HPLC-MS calculated C21H15ClF3N3O4S (M+H+): 466.1, found 466.1.
