Triphenylphosphine → (4R,5R)-4-(2-fluoro-5-((trimethylsilyl)ethynyl)pyridin-3-yl)-5-(3-fluorophenyl)oxazolidin-2-one

Participants

Reaction Conditions

Reaction Steps

To a sealable microwave vial was added (4R,5R)-4-(5-bromo-2-fluoropyridin-3-yl)-5-(3-fluorophenyl)oxazolidin-2-one (105 mg, 0.296 mmol), copper(I) iodide (1.689 mg, 8.87 μmol), triphenylphosphine (23.26 mg, 0.089 mmol) and triethylamine (4 mL). The solution was stirred and ethynyltrimethylsilane (43.6 mg, 0.443 mmol) was added and the reaction mixture was degassed with nitrogen for 10 min. To this mixture was added bis(triphenylphosphine)palladium(II) chloride (4.15 mg, 5.91 μmol) in one portion and the reaction vessel was sealed and heated to 90° C. overnight. The reaction was cooled to room temperature, the solvent was evaporated in vacuo and the crude solid was added to a silica gel column and eluted with 20% EtOAc/80% Hexanes affording (4R,5R)-4-(2-fluoro-5-((trimethylsilyl)ethynyl)pyridin-3-yl)-5-(3-fluorophenyl)oxazolidin-2-one (77 mg, 0.207 mmol, 69.9% yield) as an off white solid. 1H-NMR (CDCl3, 400 MHz) δ 8.35 (s, 1H), 8.04 (dd, J=8.0, 4.0, 1H), 7.47-7.41 (m, 1H), 7.18-7.12 (m, 3H), 5.44 (brs, 1H), 5.36 (d, J=4.0, 1H) 5.00 (d, J=5.0, 1H), 0.30 (s, 9H), LC/Mass spec. (Analytical HPLC method 2): RT=2.23 min. Mass=373.19 (MH)+.

Provenance & Evidence