Sulfuric Acid → HCID 538048, compound

HRID 1647354Notes

Reaction equation

HRID 1647354 reaction equation
[C:1]([O:4][C:5](=[O:7])[CH3:6])(=O)[CH3:2].S(=O)(=O)(O)O.[CH2:13]1[CH:18]2CC3[O:22][C:23](=O)[CH:16]([CH2:17]2)[CH2:15][CH:14]1[CH2:21]3>C1CCCCC1>[C:5]([O:4][CH:1]1[CH:18]2[CH2:17][CH:16]3[CH2:15][CH:14]([CH2:21][CH:2]1[C:23]3=[O:22])[CH2:13]2)(=[O:7])[CH3:6]

Participants

5

Reactant 3

HCID 1118Sulfuric Acid2×HCID 7918Acetic AnhydrideHCID 5567274-Oxatricyclo[4.3.1.13,8]undecan-5-one

Product 1

HCID 538048HCID 538048, compound

Reagents, catalysts & solvents 1

HCID 8078CyclohexaneSolvent

Procedure

A mixture containing 4-Oxahomoadamantane-5-one (12.5 grams, 75.3 mmol), 40 mL acetic anhydride, and 100 mL cyclohexane was charged to a 250-mL round-bottom flask and heated to reflux with a heating mantle. Concentrated sulfuric acid (0.52 grams, 5.4 mmol) was added dropwise from the top of the condenser with magnetic stirring. After 40 hours of reflux, about 5% of the 4-Oxahomoadamantan-5-one was converted to the products. More concentrated H2SO4 was added (15.8 grams, 158 mmol) in the same fashion. This separated the reaction mixture into a top grayish layer of mostly cyclohexane and a black bottom layer. Refluxing was continued for additional 6 hrs, when GC analysis of the top layer showed that the reaction was complete. After cooling, the reaction mixture was transferred into a separatory funnel and the layers were separated. The dark bottom layer was extracted with 3×50 mL cyclohexane. The combined cyclohexane solutions was washed with 100 mL each of 1N NaOH and saturated brine. GC analysis of the solution showed >99% pure two isomers of 4-Acetoxyadamantanones. After drying over anhydrous Na2SO4, removal of solvent gave 4.03 gram of 4-Acetoxyadamantanone as a yellowish oil. Crushed ice was added to the conc. H2SO4 layer separated from the reaction mixture. The resulting solution was diluted with water to ≈500 mL and extracted with 4×100 mL CH2Cl2. The combined yellow CH2Cl2 solutions was washed with 1N NaOH (2 ×200 mL), water (100 mL), and saturated brine (100 mL). GC analysis of the solution showed that it was predominantly 4-Acetoxyadamantanone with small amounts of 4-Hydroxyadamantanones. Removal of solvent by rotary evaporation gave 7.24 grams of a red oil.

Workup

  1. additionwas charged to a 250-mL round-bottom flask
  2. temperatureheated
  3. temperatureto reflux with a heating mantle
  4. temperatureAfter 40 hours of reflux
  5. customThis separated the reaction mixture into a top grayish layer of mostly cyclohexane
  6. temperatureRefluxing
  7. temperatureAfter cooling
  8. customthe reaction mixture was transferred into a separatory funnel
  9. customthe layers were separated
  10. extractionThe dark bottom layer was extracted with 3×50 mL cyclohexane
  11. washThe combined cyclohexane solutions was washed with 100 mL each of 1N NaOH and saturated brine
  12. dry with materialAfter drying over anhydrous Na2SO4, removal of solvent

Sources & evidence

ORD record
ord-f28620f5c3654093a6e772a9934732cf
Source dataset
uspto-grants-1995_07
Patent number
US05430193

Reaction notes

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