Hydrochloric Acid → 3-(4-Methyl-4-pentenyl)pyridine

Participants

Reaction Steps

A suspension of 7.0 g of sodium hydride (60% dispersion in oil) in 75 mL of dry dimethylsulfoxide was stirred at 75° C. under argon for 45 minutes, at which time the evolution of hydrogen had ceased. After the solution was cooled, 61 g of methyltriphenylphosphonium bromide was added and the mixture was stirred at room temperature for 30 minutes before the addition of 25 g of 5-(3-pyridinyl)-2-pentanone in 125 mL of dimethylsulfoxide. The reaction was then stirred at room temperature overnight. After the addition of 1L of 1N hydrochloric acid solution, the precipitated triphenylphosphine oxide was removed by filtration, and the filtrate was basified with 110 mL of 10N sodium hydroxide. The product was extracted with dichloromethane (4×300 ml) and the extracts were washed with brine, then were combined, dried (K2CO3) and evaporated to give 25 g of crude product. The material was purified by HPLC (ethyl acetate:hexane: 1:1) to yield 17.5 g of 3-(4-methyl-4-pentenyl)pyridine as a colorless oil.

Provenance & Evidence