Hydrochloric Acid → 3-BENZOYLTHIOPHENE

Participants

Reaction Conditions

Reaction Steps

The solution containing 0.937 mL (10 mmol) of 3-bromothiophene, 3 mL of tetrahydrofuran, and 8 mL of ether was cooled to −78° C. under N2. To the cooled solution was then added 4 mL of n-BuLi ([2.5] M in hexane) drop wise, while maintaining the reaction temperature below −70° C. The reaction solution turned to light yellow suspension. The suspension was allowed to stir 15 min at <−70° C. After 15 min, a solution containing 1.02 mL (10 mmol) of benzonitrile and 3 mL of tetrahydrofuran was added drop wise while maintaining the reaction temperature below −70° C. After the addition, the reaction suspension was allowed to stir 1 hr at −78° C. and slowly warmed to −10° C. over 2 hr. After 2 hr the reaction was stopped by adding 10 mL of H2O and 30 mL of 2N HCl. The aqueous solution was separated from the organic phase. The aqueous phase was washed with ether (2>20 mL). The washed aqueous solution was then heated to reflux for 2 hr. After 2 hr, the solution was cooled. To the cooled solution was added 30 mL of ether. The aqueous solution was removed. The organic solution was finally washed with brine, dried over MgSO4, and concentrated under reduced pressure. The concentrated sample was purified by flashy chromatography (hexane:ethyl acetate, from 4 to 6 % ethyl acetate over 16 column volume) to obtain 1.36 gm (72.3%) of a clear oil; 1H NMR 300 MHz (CDCl3) δ 7.93 (t, 1H), 7.83-7.86 (m, 2H), 7.26-7.61 (m, 5H).

Provenance & Evidence