Triisopropyl borate → (2-(N-(tert-Butyl)sulfamoyl)-5-isobutylthiophen-3-yl)boronic acid

Participants

Reaction Conditions

Reaction Steps

5-iso-Butyl-N-tert-butylthiophene-2-sulfonamide (10.6 g, 0.039 mol, see step (b) above) was dissolved in THF (165 mL) under N2 and then cooled to −78° C. n-BuLi (1.6 M, 60.19 mL, 0.096 mol) was added via a syringe. The reaction mixture was stirred at −20° C. for 4 h. The tri-iso-propylborate (13.3 mL, 0.058 mol) was then added via a syringe and the reaction mixture was stirred overnight at room temperature. The reaction was quenched with 2 M HCl (20 mL). The organic phase was separated and the water phase was extracted with EtOAc (3×100 mL). The combined organic phase was washed with brine, dried and concentrated in vacuo. The product was used without further purification. MS (ESI+) m/z: 236.8

Provenance & Evidence