Sodium Azide → HCID 178506094, Verbindung

Beteiligte Stoffe

Reaktionsschritte

Anhydrous zinc bromide (93.5 g, 415 mmol, 0.99 equiv.), sodium azide (29.8 g, 458 mmol, 1.1 equiv.) and water (750 ml) were added to 3,5-bis(trifluoromethyl)benzonitrile (100.0 g, 418 mmol, 1.00 equiv.). The resulting suspension was stirred for 10 days at ambient temperature. The completion of the reaction was confirmed by reversed phase HPLC on a Waters Novapak C18 column (3.9×150 mm) eluting with a linear gradient from 40% to 100% acetonitrile in 250 mM triethylammonium acetate buffer pH 6.5 in 15.00 minutes with a flow rate of 1.0 mL/min, detection at λ=270 nm, product retention time 2.0 min., educt retention time 6.5 min. Ethyl acetate (3.8 ltr.) and 10% citric acid in water were added and the resulting mixture was vigorously stirred for 15 minutes. The aqueous phase was separated and extracted with ethyl acetate (2×900 ml). The organic phases were combined and evaporated to dryness. The resulting solid was stirred in aqueous NaOH solution (0.25 M, 3.8 ltr.) for 30 minutes to give a suspension, which was filtered. The filtrate was acidified with aqueous HCl (375 ml conc. hydrochloric acid and 375 ml water) which caused the product to precipitate as a fine white powder. The product was collected by filtration after one hour, washed with cold hexanes (100 ml) and dried in a desiccator under vacuum, yield 72.7 g (62%) of compound (8) as white crystalline powder. The purified product had a purity of 100% by reversed phase HPLC as depicted in FIG. 4. 1H NMR (300 MHz, d6-DMSO) δ 8.26 (s, 1H), 8.59 (s, 1H), m.p. 179° C. The product can be recrystallized from toluene.

Herkunft & Nachweise