Sulfuric Acid → HCID 90431845, compound

Participants

Reaction Steps

Under a nitrogen atmosphere, methyl magnesium bromide (0.97 mol/L, tetrahydrofuran solution, 8.5 ml, 8.25 mmol) was placed into a 100-ml flask equipped with a stirring apparatus, a dropping funnel, and a thermometer, and cooled to −10° C. (1S*,2S*)-1-Methyl-2-[(R*)-1-phenylethyl]cyclopropane carbaldehyde (1.03 g, 5.5 mmol) was placed into the dropping funnel, and added dropwise in 5 minutes with the temperature kept at −10° C. After stirring for 60 minutes, a 20% aqueous sulfuric acid solution (4.5 g) was added. After stirring for 10 minutes, the aqueous layer was separated, and the organic layer was washed twice with water (10 ml). The solvent was recovered under reduced pressure to obtain a condensed residue. This residue was purified by silica gel column chromatography (hexane:ethyl acetate=10:1). (R*)-1-[(1S*,2S*)-1-Methyl-2-((R*)-1-phenylethyl)cyclopropyl]ethanol (0.75 g, 3.68 mmol, 67% yield) was obtained as the main isomer, and (S*)-1-[(1S*,2S*)-1-methyl-2-((R*)-1-phenylethyl)cyclopropyl]ethanol (0.205 g, 1.0 mmol, 18% 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