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

Temperature

-75 °C

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.

1. additionwas added dropwise
2. customthe temperature below −65° C
3. customthe temperature below −65° C
4. temperatureto warm to room temperature
5. waitsit at room temperature for 2 h
6. customwas then partitioned between diethyl ether and water
7. extractionThe product was extracted with diethyl ether
8. customthe organic phase was dried
9. concentrationconcentrated under vacuum

ORD record

ord-2bf0794e44ac404b9806187a758ed0a3

Source dataset

uspto-grants-2015_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09149038B2