Lawesson's reagent → HCID 59275510, compound

Participants

Reaction Steps

The reaction was run in two batches and combined for workup. In the first batch, Lawesson's reagent (27 mg, 0.067 mmol) was added to a solution of 2-(4-fluorophenyl)-5-isopropoxy-6-(methylsulfonamido)benzofuran-3-carboxamide (35 mg, 0.086 mmol) in THF (1.2 mL). The reaction was stirred at r.t. for 2 h, at which point additional Lawesson's reagent (8 mg, 0.020 mmol) was added. In the second batch, Lawesson's reagent (129 mg, 0.32 mmol) was added to a solution of 2-(4-fluorophenyl)-5-isopropoxy-6-(methylsulfonamido)benzofuran-3-carboxamide (125 mg, 0.31 mmol) in THF (3 mL) was stirred at r.t. for 1.5 h. The two batches were then combined and partitioned between EtOAc (50 mL) and water (10 mL). The organic phase was washed with sat'd NaHCO3 and brine, dried over Na2SO4, filtered, and concentrated to give a yellow oil. The residue was purified by silica gel chromatography (Biotage 25+S silica gel cartridge, gradient elution: 20% to 80% EtOAc/hexanes over 20 column volumes, fraction collection at λ=320 nm) to give 48 mg (29% yield) of the title compound. 1H NMR (300 MHz, CDCl3) δ ppm 7.76-7.87 (m, 2H) 7.71 (d, J=5.86 Hz, 2H) 7.53 (br. s., 1H) 7.13-7.23 (m, 2H) 6.97 (s, 1H) 6.90 (br. s., 1H) 4.74 (dt, J=12.08, 6.04 Hz, 1H) 2.93 (s, 3H) 1.40 (d, J=6.22 Hz, 6H). LC/MS was performed by using Shimadzu-VP instrument with UV detection at 220 nm and Waters Micromass. LC/MS method: solvent A=5% CH3CN/95% H2O/0.1% NH4OAc, solvent B=95% CH3CN/5% H2O/0.1% NH4OAc, start % B=0, final % B=100, gradient time=2 min, stop time=3 min, flow rate=5 ml/min, column: XBridge C18 5 μm 4.6×50 mm; HPLC Rt=1.39 min, (ES+) m/z (MH+)=423.

Provenance & Evidence