3-Bromobenzonitrile → 5-(3-bromophenyl)-1H-1,2,3,4-tetrazole

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

3-Bromobenzonitrile (2.49 g, 13.7 mmol) and azidotrimethylsilane (3.14 g, 27.3 mmol) were stirred in anhydrous toluene (100 mL) under argon at ambient temperature. To this was added dibutyltin oxide (341 mg, 1.37 mmol) and the resulting reaction was fitted with a reflux condenser and heated with stirring at 110° C. for 3 h. Upon cooling, the reaction mixture was concentrated in vacuo, and then concentrated to dryness twice following the addition of MeOH (ca. 25 mL each). The crude reaction mixture was dissolved in EtOAc (300 mL) and washed with H2O (2×100 mL). The organic phase was washed with 1N aqueous NaOH (4×75 mL), the combined basic aqueous portions were treated with 4N HCl to obtain an endpoint of pH=4 and the acidic aqueous phase was extracted with EtOAc (4×100 mL washes). The combined EtOAc layers were dried (MgSO4), filtered, and concentrated in vacuo to obtain 5-(3-bromophenyl)-2H-tetrazole as a white solid.

Herkunft & Nachweise