Sodium Bicarbonate → 7,8-Difluoro-1,2,3,4-tetrahydrocyclopent[b]indole

A stirred solution of 7,8-difluoro-1,2,3,3a,4,8a-hexahydro-8a-hydroxy-cyclopent[b]indole (1.1 g, 5.2 mmol), in dichloromethane (150 mL) was cooled to 0° C. Trifluoroacetic acid (20 drops) was added and the reaction mixture was stirred at room temperature for 18 h. The reaction mixture was poured onto saturated sodium hydrogen carbonate solution (20 mL) and extracted with dichloromethane (3×50 mL). The organic extracts were combined, dried (magnesium sulfate), filtered, concentrated in vacuo and purified by column chromatography [SiO2; ethyl acetate-heptane (1:5)]to give the product (0.78 g, 78%) as a white crystalline solid. IR νmax (Nujol)/cm−1 3467, 2925, 2854, 1565, 1515, 1450, 1348, 1327, 1244, 1053, 1025, 977, 857, 783, 630 and 516; NMR δH (400 MHz, CDCl3) 2.49-2.58 (2H, m), 2.79-2.87 (2H, m), 2.9-2.96 (2H, m), 6.81-6.95 (2H, m), and 7.83 (1H), br s).

1. extractionextracted with dichloromethane (3×50 mL)
2. dry with materialdried (magnesium sulfate)
3. filtrationfiltered
4. concentrationconcentrated in vacuo
5. custompurified by column chromatography [SiO2

ORD record

ord-8d1a0e6eedd0411196b049951a93f307

Source dataset

uspto-grants-2004_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06706750B1