Triethylamine → (1S)-1-(2,6-Dichloro-3-fluorophenyl)ethyl methanesulfonate

Participants

Reaction Conditions

Reaction Steps

To a cooled (ice bath) solution of (S)-1-(2,6-Dichloro-3-fluorophenyl)ethanol (4.00 g, 16.3 mmol) and triethylamine (3.4 mL, 24 mmol) in toluene (20 mL) was added dropwise methanesulfonyl chloride (1.64 mL, 21.1 mmol). A white suspension formed that was stirred at 0-5° C. for 35 min. The reaction mixture was diluted with H2O (20 mL), the layers were separated, and the aqueous layer was extracted with toluene (10 mL). The combined organic layers were washed with water (2×10 mL) and concentrated under vacuum at 40-45° C. to give the title compound as colorless oil containing ≈0.2 eq. of toluene according to 1H NMR. This material was used directly in the next step. 1H NMR (CDCl3, 400 MHz): δ=7.33 (dd, J=9.0, 4.9 Hz, 1H), 7.12 (dd, J=9.0, 8.0 Hz, 1H), 6.45 (q, J=6.8 Hz, 1H), 2.91 (s, 3H), 1.84 (d, J=6.8 Hz).

Provenance & Evidence