Methyl iodide → Ethyl 2-(4,4-difluorocyclohexyl)-2-methylpropanoate

To a solution of Intermediate 232A (0.27 g, 1.226 mmol) in THF (5 mL) was added LDA (1.226 mL, 2.452 mmol, 2M in THF) dropwise at −78° C. and the resulting solution was stirred at the same temperature for 45 min. MeI (0.307 mL, 4.90 mmol) was then added at −78° C. and the reaction mixture was allowed to warmed to RT and stir for 12 h. The reaction mixture was quenched with a saturated aqueous solution of NH4Cl and extracted with EtOAc (2×25 mL). The combined organic layer was dried over Na2SO4, filtered and the filtrate concentrated. The crude product was purified by silica gel chromatography (12 g REDISEP® column, eluting with 2% EtOAc in hexane.) Fractions containing the product were combined and evaporated to afford Intermediate 232B as a pale yellow liquid. (0.15 g, 55%). 1H NMR (300 MHz, DMSO-d6) δ ppm 4.07 (q, J=7.2 Hz, 2H), 2.01 (d, J=12.1 Hz, 2H), 1.92-1.74 (m, 2H), 1.73-1.53 (m, 4H), 1.31-1.20 (m, 2H), 1.11 (br. s., 4H), 1.03 (d, J=2.6 Hz, 6H).

1. stirringstir for 12 h
2. customThe reaction mixture was quenched with a saturated aqueous solution of NH4Cl
3. extractionextracted with EtOAc (2×25 mL)
4. dry with materialThe combined organic layer was dried over Na2SO4
5. filtrationfiltered
6. concentrationthe filtrate concentrated
7. customThe crude product was purified by silica gel chromatography (12 g REDISEP® column, eluting with 2% EtOAc in hexane.) Fractions
8. additioncontaining the product
9. customevaporated

ORD record

ord-6e9ec1f97c6e4008ace3c368ee7159e2

Source dataset

uspto-grants-2016_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09273058B2