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. 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 HCl (2 M, 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.

Provenance & Evidence