Cesium carbonate → (S)-1-(2-methyl-6-(5-(methylsulfonyl)pyridin-2-yl)-5-propoxy-3,4-dihydroquinolin-1(2H)-yl)ethanone

Participants

Reaction Conditions

Reaction Steps

A mixture of (S)-1-(2-methyl-5-propoxy-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-3,4-dihydroquinolin-1 (2H)-yl)ethanone (0.055 g, 0.147 mmol), 2-bromo-5-(methylsulfonyl)pyridine (0.037 g, 0.155 mmol), XPhos Precatalyst 2nd Generation (0.012 g, 0.015 mmol), and cesium carbonate (0.144 g, 0.442 mmol) in 1,4-dioxane (2.0 mL) and water (0.40 mL) was heated in the microwave at 100° C. for 1.5 h. The reaction mixture was filtered through Celite and concentrated to afford an orange oil. This material was purified via column chromatography on silica gel (Biotage 25 g column, gradient elution with 25-100% ethyl acetate-hexane) to afford (S)-1-(2-methyl-6-(5-(methylsulfonyl)pyridin-2-yl)-5-propoxy-3,4-dihydroquinolin-1(2H)-yl)ethanone (0.016 g, 27%) as a tan solid. 1H NMR (300 MHz, DMSO-d6) δ ppm 0.85 (t, J=7.33 Hz, 3H), 1.07 (d, J=6.45 Hz, 3H), 1.32-1.50 (m, 2H), 1.56 (dt, J=14.07, 7.04 Hz, 2H), 2.14 (s, 3H), 2.19-2.33 (m, 1H), 2.79-2.94 (m, 1H), 3.37 (s, 3H), 3.50 (td, J=6.30, 2.64 Hz, 2H), 4.51-4.75 (m, 1H), 7.33 (br d, J=8.50 Hz, 1H), 7.64 (d, J=8.50 Hz, 1H), 8.08-8.21 (m, 1H), 8.36 (dd, J=8.50, 2.35 Hz, 1H), 9.14 (d, J=2.05 Hz, 1H). MS (ESI, pos. ion) m/z 403 [M+H]+.

Provenance & Evidence