Sulfuric Acid → HCID 90431875, compound

Participants

Reaction Conditions

Reaction Steps

Under a nitrogen atmosphere, a diethylzinc solution in toluene (concentration: 15% by weight, 37.9 g, 46.0 mmol) was placed into a 200-ml flask equipped with a stirring apparatus, a dropping funnel, and a thermometer, and cooled to −20° C. Chloroiodomethane (16.22 g, 92.0 mmol) was placed into the dropping funnel, and added dropwise with the temperature kept between −15 to −20° C. After completion of the dropwise addition, the mixture was stirred at −10 to −15° C. for 30 minutes, and then cooled to −25° C. (E)-2-Methyl-4-phenylpent-2-ene-1-ol (4.11 g, 23.3 mmol) was added dropwise over a period of 60 minutes in the range from −20 to −25° C. After completion of the dropwise addition, the stirring was continued at −15 to −25° C. for 60 minutes. Next, a 20% aqueous sulfuric acid solution (17.0 ml) was added. After stirring for 10 minutes, the aqueous layer was separated. The organic layer was washed twice with water (20 ml), and the solvent was recovered under reduced pressure to obtain a condensed residue. This residue was purified by silica gel column chromatography (hexane:ethyl acetate=8:2). [(1R*,2S*)-1-Methyl-2-((R*)-1-phenylethyl)cyclopropyl]methanol (1.85 g, 9.74 mmol, 42% yield) was obtained as the main isomer, and [(1R*,2S*)-1-methyl-2-((S*)-1-phenylethyl)cyclopropyl]methanol (0.55 g, 2.9 mmol, 12% yield) was obtained as a minor isomer. The relative configurations of the main isomer and the minor isomer were determined by NOESY measurement.

Provenance & Evidence