Sulfuric Acid → HCID 90431875, compound

HRID 929423Notes

Reaction equation

HRID 929423 reaction equation
[CH2:1]([Zn]CC)C.C1(C)C=CC=CC=1.ClCI.[CH3:16]/[C:17](=[CH:20]\[CH:21]([C:23]1[CH:28]=[CH:27][CH:26]=[CH:25][CH:24]=1)[CH3:22])/[CH2:18][OH:19].S(=O)(=O)(O)O>>[CH3:16][C@@:17]1([CH2:18][OH:19])[CH2:1][C@H:20]1[C@H:21]([C:23]1[CH:24]=[CH:25][CH:26]=[CH:27][CH:28]=1)[CH3:22]

Participants

6

Conditions

Temperature
-20 °C

Procedure

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.

Workup

  1. customequipped with a stirring apparatus, a dropping funnel
  2. additionadded dropwise with the temperature
  3. customkept between −15 to −20° C
  4. additionAfter completion of the dropwise addition
  5. additionwas added dropwise over a period of 60 minutes in the range from −20 to −25° C
  6. additionAfter completion of the dropwise addition
  7. waitthe stirring was continued at −15 to −25° C. for 60 minutes
  8. stirringAfter stirring for 10 minutes
  9. customthe aqueous layer was separated
  10. washThe organic layer was washed twice with water (20 ml)
  11. customthe solvent was recovered under reduced pressure
  12. customto obtain a condensed residue
  13. customThis residue was purified by silica gel column chromatography (hexane:ethyl acetate=8:2)

Sources & evidence

ORD record
ord-0f5d2367ec5f48a793984a5b5c10692a
Source dataset
uspto-grants-2016_03
Patent number
US09296675B2

Reaction notes

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