Trifluoroacetic acid → ethyl 6,6-difluoro-4,5,6,7-tetrahydro-1H-indole-2-carboxylate

Temperature

0 °C

Into a 500-mL 3-necked round-bottom flask was placed a solution of 113k (18 g, 73.40 mmol, 1.00 equiv) in dichloromethane (200 mL) and CF3COOH (41.9 g, 367.48 mmol, 5.00 equiv), followed by the addition of triethylsilane (25.6 g, 220.16 mmol, 3.00 equiv) dropwise with stirring at 0° C. over 20 min (FIG. 14). The resulting solution was stirred at room temperature for 4 h, adjusted pH to 7 with saturated aqueous sodium bicarbonate and extracted with 1×200 mL of dichloromethane. The combined organic layers were washed with 1×100 mL of water and 1×100 mL of brine, dried over anhydrous sodium sulfate and concentrated under vacuum. The crude product was purified by Flash-Prep-HPLC to afford 10 g (59%) of 113l as a white solid.

1. customInto a 500-mL 3-necked round-bottom flask was placed
2. stirringThe resulting solution was stirred at room temperature for 4 h
3. extractionextracted with 1×200 mL of dichloromethane
4. washThe combined organic layers were washed with 1×100 mL of water and 1×100 mL of brine
5. dry with materialdried over anhydrous sodium sulfate
6. concentrationconcentrated under vacuum
7. customThe crude product was purified by Flash-Prep-HPLC

ORD record

ord-8595eb224aba45e791437523685123e4

Source dataset

uspto-grants-2015_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09115152B2