Gamma-Valerolactone → HCID 86658323, compound

Participants

Reaction Steps

At room temperature, 6.0 ml (12.0 mmol) of a 2.0 M trimethylaluminium solution in heptane are added dropwise to a solution of 0.78 g (4.0 mmol) of benzophenone hydrazone in 10 ml of dichloromethane, and the mixture is stirred for 30 min. A solution of 0.40 g (4.0 mmol) of γ-valerolactone in 5 ml of dichloromethane is then added dropwise to the reaction mixture. The reaction mixture is stirred at reflux for 2 h. A further 0.12 g (1.20 mmol) of γ-valerolactone is added, and the reaction mixture is stirred at reflux for 1 h. After cooling, dichloromethane/water is added to the reaction mixture. The organic phase is separated off and the aqueous phase is extracted with dichloromethane. The combined organic phases are dried over Na2SO4 and freed from the solvent under reduced pressure. Purification by column chromatography on silica gel (cyclohexane/ethyl acetate) gives 0.9 g (76%) of the desired product; (log P(HCOOH): 2.25); 1H-NMR (ppm): δ (DMSO-d6)=1.01 (d, 1H), 1.10 (d, 2H), 1.45-1.72 (m, 2H), 2.16-2.26 (m, 1H), 2.75-2.86 (m, 1H), 3.51-3.57 (m, 0.3H), 3.65-3.71 (m, 0.7H), 4.43 (d, 0.3H), 4.52 (d, 0.7H), 7.25-7.62 (m, 10H), 8.99 (s, 1H); LC-MS: m/z=297 [M+H]+

Provenance & Evidence