Propargyl alcohol → HCID 18616195, compound

Participants

Reaction Steps

To a solution of propargyl alcohol (166, Aldrich, 1.46 mL, 25 mmol) in anhydrous tetrahydrofuran (10 mL), was added 0.5M 9-BBN in THF (Aldrich, 100 mL, 50 mmol) through an addition funnel at 0° C. under nitrogen over a period of 1 hour. After the addition was complete, the flask was stored in a 5° C. refrigerator under nitrogen for 18 hours. The reaction mixture was warmed to room temperature under nitrogen. To the reaction mixture was added 4-bromotolunitrile (compound 160, Aldrich, 5.88 g, 30 mmol), tetrakis(triphenyl-phosphine)palladium (0) (Aldrich, 1.00 g, 0.86 mmol), and 2M sodium hydroxide solution (25 mL, 50 mmol). The reaction mixture was degassed with nitrogen three times, and then refluxed at 65° C. for 2 hours. The reaction mixture was cooled to room temperature. 30% hydrogen peroxide in water (30 mL) and 2M sodium hydroxide solution (10 mL) was added slowly. Copius amounts of gas released during addition of hydrogen peroxide:. The resulting solution was stirred at room temperature for an additional hour. The reaction mixture was extracted with ethyl acetate. The combined extracts were washed with brine and then dried over Na2SO4. After filtration and evaporation, the crude product was purified on a silica gel column, eluting with hexane-ethyl acetate (4:1 and 3:1). The product 167 was obtained as colorless oil (1.05 g, 24% yield). TLC Rf 0.30 (Hexane: EtOAc 1:1); 1H-NMR (400 MHz, CDCl3): δ7.58 (d, 2H, J 8.1 Hz), 7.29 (d, 2H, J 8.1 Hz), 5.82 (dt, 1H, J 15.6 Hz, J 6.4 Hz), 5.71 (dt, 1H, J 15.6 Hz, J 5.4 Hz), 4.14 (d, 2H, J 5.4 Hz), 3.44 (d, 2H, J 6.4 Hz), 1.62 (s, 1H).

Provenance & Evidence