2,2-Difluoro-1,3-benzodioxole → HCID 72221137, compound

Participants

Reaction Conditions

Reaction Steps

2,2-Difluorobenzo[d][1,3]dioxole (6 g, 38.0 mmol) was dissolved in tetrahydrofuran (100 mL) and cooled to −75° C. sec-Butyllithium (1.4 M in cyclohexane; 29.8 mL, 41.7 mmol) was added dropwise, keeping the temperature below −65° C. The reaction mixture was then stirred at −75° C. for 1 h to ensure complete deprotonation. 2-Isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (7.06 g, 38.0 mmol) was then added to the reaction mixture dropwise keeping the temperature below −65° C. The reaction mixture was then allowed to warm to room temperature and sit at room temperature for 2 h and was then partitioned between diethyl ether and water. The aqueous phase was acidified to pH 3 with 12 N HCl. The product was extracted with diethyl ether and the organic phase was dried and concentrated under vacuum to provide the title compound as an off-white solid (7.06 g, 65.5%): 1H NMR (300 MHz, CDCl3) δ 7.43 (dd, J=7.5, 1.5 Hz, 1H), 7.13 (dd, J=7.9, 1.5 Hz, 1H), 7.05 (t, J=7.7 Hz, 1H), 1.37 (s, 12H); EIMS m/z 284.

Provenance & Evidence