Cyclohexanone → Ethyl cyclohexylideneacetate

Participants

Reaction Conditions

Reaction Steps

Triethylphosphonoacetate (5.0 g, 22.3 mmol) was dissolved in THF (25 mL) and cooled to −78° C. under a nitrogen blanket. n-Butyllithium (1.6 M in hexanes, 13.9 mL, 22.3 mmol) was added dropwise via syringe followed by the addition of 1,3-dimethyl-3,4,5,6-tetrahydro-2-(1H)-pyrimidinone (3 mL). The reaction was stirred at −78° C. for 15 minutes. A solution of cyclohexanone (1.1 g, 11.2 mmol) dissolved in THF (5 mL) was added. The mixture was allowed to warm to room temperature, and stirred for 18 hours. The reaction was diluted with 1N HCl and extracted with EtOAc, then washed with water, dried (Na2SO4), and concentrated in vacuo to provide 1.7 g (89%) of Intermediate 3 as an oil. 1H NMR (DMSO-d6) δ: 1.15 (t, J=7 Hz, 3H), 1.55 (br s, 6H), 2.2 (br s, 2H), 2.75 (br s, 2H), 4.05 (q, J=7 Hz, 2H), 5.6 (s, 1H).

Provenance & Evidence