Diisopropylamine → 6-[2-cyclopentyl-4-(3-fluoro-4-isopropylphenyl)-2-hydroxybut-3-ynyl]-2,2-dimethyl-4H-1,3-dioxin-4-one

Participants

Reaction Conditions

Reaction Steps

4-Bromo-2-fluoro-1-isopropylbenzene (5.0 g, 23.2 mmol), 6-(2-cyclopentyl-2-hydroxybut-3-ynyl)-2,2-dimethyl-4H-1,3-dioxin-4-one (5.56 g, 21.0 mmol) were dissolved in anhydrous DMF (30 mL). To this solution, CuI (120 mg, 0.63 mmol), Pd(PPh3)2Cl2 (0.59 g, 0.84 mmol), and diisopropylamine (60 mL), were added sequentially. The mixture was then heated at 90° C. for 20 min before it was cooled down to 25° C. The reaction was diluted with EtOAc (150 mL) and washed with aqueous NH4Cl, brine, and dried over Na2SO4. The solvent was removed in vacuo and the residue was purified by flash column chromatography (0-40% EtOAc in hexanes) to give the desired product (7.5 g, 81% yield). 1H NMR (CDCl3, 300 MHz) δ: 1.22-1.28 (m, 8H), 1.69-1.74 (m, 10H), 1.80-1.86 (m, 2H), 2.19-2.26 (m, 1H), 2.62-2.70 (m, 2H), 3.18-3.25 (m, 1H), 5.46 (s, 1H), 7.00 (dd, J=10.61, 1.52 Hz, 1H), 7.09-7.11 (m, 1H), 7.18 (t, J=7.71 Hz, 1H).

Provenance & Evidence