Triethylamine → (S)-N-((3-(3-fluoro-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)-2-oxooxazolidin-5-yl)methyl)acetamide

Participants

Reaction Steps

A suspension of (5S)—N-[3-(3-fluoro-4-iodo-phenyl)-2-oxo-oxazolidin-5-ylmethyl]acetamide 108 (20.0 g, 52.8 mmol, prepared as described in Example 1, above) in anhydrous 1,4-dioxane (130 mL) was treated with 4,4,5,5-tetramethyl-[1,3,2]dioxaborolane (10.2 g, 11.6 mL, 80.0 mmol, 1.5 equiv) and triethylamine (16.0 g, 22.4 mL, 158.4 mmol, 3.0 equiv) at room temperature. The resulting reaction mixture was degassed three times under a steady stream of argon before being treated with dichloro[1,1′-bis(diphenylphosphino)ferrocene]palladium (II) (Pd(dppf)2Cl2, 1.32 g, 1.6 mmol, 0.03 equiv) at room temperature. The resulting reaction mixture was degassed three times under a steady stream of argon before being warmed to reflux for 7 h. When HPLC/MS showed the reaction was complete, the reaction mixture was cooled to room temperature before being treated with water (100 mL) and ethyl acetate (100 mL). The two layers were separated, and the aqueous layer was extracted with ethyl acetate (2×50 mL). The combined organic extracts were washed with water (2×50 mL) and saturated aqueous NaCl (50 mL), dried over MgSO4, and concentrated in vacuo. The residual brown oil was further dried in vacuo to afford the desired (5S)—N-{3-[3-fluoro-4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenyl]-2-oxo-oxazolidin-5-ylmethyl}acetamide 123 (18.8 g, 94%) as brown solids. This product was directly used in subsequent reactions without further purification. C18H24BFN2O5, HPLC/MS (ESI) m/e 379 (M++H).

Provenance & Evidence