Dichloromethane → (R)-N-((S)-1-(4-(1-ethoxyvinyl)-2-fluorophenyl)ethyl)-2-methylpropane-2-sulfinamide

Participants

Reaction Conditions

Reaction Steps

To a microwave vial with stir bar was added (R)—N—((S)-1-(4-bromo-2-fluorophenyl)ethyl)-2-methylpropane-2-sulfinamide (1 g, 3.10 mmol) followed by the addition of tributyl(1-ethoxyvinyl)stannane (2.24 g, 6.21 mmol), TEA (1.3 mL, 9.31 mmol) and PdCl2(dppf).CH2Cl2 adduct (0.127 g, 0.155 mmol). To the solids was then added toluene (10 mL). Vial capped and heated by microwave irradiation at 100° C. for 30 min. To this reaction mixture was added 1 ml of TFA to try to convert vinyl ether to the ketone which was unsuccessful. Resulting reaction mixture allowed to stir 5 min at room temperature. Reaction mixture was then quenched with a saturated solution of NaHCO3 to pH 8. Aqueous mixture extracted with EtOAc. Organic phases combined, washed with water, brine, dried (Na2SO4), filtered and concentrated onto silica gel. Silica gel column chromatography (EtOAc/Heptane 40 to 100%) provided (R)—N—((S)-1-(4-(1-ethoxyvinyl)-2-fluorophenyl)ethyl)-2-methylpropane-2-sulfinamide (0.60 g, 1.91 mmol, 62% yield) as a yellow viscous residue. 1H NMR (400 MHz, CDCl3) δ 1.20 (s, 9H) 1.43 (t, J=6.94 Hz, 3H) 1.56-1.63 (m, 5H) 3.36 (d, J=3.13 Hz, 1H) 3.92 (q, J=6.96 Hz, 2H) 4.23 (br. s., 1H) 4.65 (s, 1H) 4.79-4.91 (m, 1H) 7.30 (s, 2H) 7.40 (d, J=8.02 Hz, 1H).

Provenance & Evidence