Imidazole → (R)-ethyl 5-((tert-butyldiphenylsilyl)oxy)hexanoate

To a solution of (R)-ethyl 5-hydroxyhexanoate (5 g, 31.2 mmol) in DMF (100 mL) at 0° C. was added imidazole (3.19 g, 46.8 mmol) followed by tert-butylchlorodiphenylsilane (12.00 mL, 46.8 mmol) and the resulting mixture was stirred at room temp for 16 h. Water (30 mL) was then added and the mixture was extracted with ether (2×100 mL). Ether layer was then washed with brine (50 mL), dried (Na2SO4), filtered and concentrated. The residue was purified via Biotage (0-10% EtOAc/hexane) to afford (R)-ethyl 5-((tert-butyldiphenylsilyl)oxy)hexanoate (10 g, 25.09 mmol, 80% yield) as clear viscous liquid. 1H NMR (500 MHz, CDCl3) δ 7.73-7.68 (m, 4H), 7.48-7.36 (m, 6H), 4.13 (q, J=7.2 Hz, 2H), 3.96-3.76 (m, 1H), 2.31-2.16 (m, 2H), 1.72-1.62 (m, 2H), 1.58-1.40 (m, 2H), 1.27 (t, J=7.1 Hz, 3H), 1.12-1.05 (m, 12H).

1. extractionthe mixture was extracted with ether (2×100 mL)
2. washEther layer was then washed with brine (50 mL)
3. dry with materialdried (Na2SO4)
4. filtrationfiltered
5. concentrationconcentrated
6. customThe residue was purified via Biotage (0-10% EtOAc/hexane)

ORD record

ord-ff29be5524da4ae4a4378d035ff5fd3e

Source dataset

uspto-grants-2016_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09273067B2