Hydrochloric Acid → 2-[(1-tert-Butyl)-1H-tetrazol-5-yl]phenylboronic acid

Participants

Reaction Steps

To dry Mg turnings (76 mg, 3.13 mmol) in THF (1 mL) was added a solution of 1-tert-butyl-5-(2-bromophenyl)-1H-tetrazol (733 mg, 2.61 mmol) in THF (1.5 mL). 1,2-Dibromoethane (20 μL) was added and the mixture was warmed slightly with a heat gun. After 5 min, triisopropyl borate (564 mg, 3.00 mmol) was added and the mixture was stirred at room temperature for 23 h. Ice and and 0.5N HCl (7 mL) were added and the mixture was stirred at for 5 min. The mixture was extracted with ether, and the combined extracts were extracted with 1N KOH (10 mL). The aqueous extracts were filtered and acidified to pH 3 with 2N HCl. The precipitate was collected by filtration to give 306 mg (48%) of product as an off-white solid, mp 112°-115° C.

Provenance & Evidence