Sodium hydride → HCID 54200668, compound

Participants

Reaction Steps

47.6 g (0.20 mol) of triethyl 2-phosphonopropionate was added dropwise under nitrogen to a cooled and stirred suspension of 4.8 g (0.20 mol) of sodium hydride in 300 ml of THF and stirring continued for 30 min. at room temperature. After addition of 30 g (0.18 mol) of 1-(2,2,3-trimethylcyclopent-3-enyl)propan-2-one, prepared from campholenic aldehyde as known per se, and 46 hours of more stirring, the reaction mixture was poured into 400 ml of ice-cold 1N hydrochloric acid and extracted with 2×300 ml of MTBE. The extract was washed with 5×350 ml of brine, dried (MgSO4) and concentrated in vacuo. The distillation at 90-97° C./0.065-0.075 Torr yielded 13 g of the product which was further purified by flash chromatography on silica gel (eluent: hexane/MTBE 15:1) to give 6.4 g (14% yield) of2,3-dimethyl-4-(2,2,3-trimethylcyclopent-3-enyl)but-2-enoic acid ethyl ester.

Provenance & Evidence