Réaction #57418

ord-ddf74302bee648e59cbd1a29877f6a4d

Solvants

Conditions de réaction

Température
80°CELSIUS
Conditions détaillées
See reaction.notes.procedure_details.

Traitement

  1. 1
    Autreto give a hazy solution
  2. 2
    AutreThe reaction vessel was fitted with a reflux condenser/argon inlet
  3. 3
    TempératureAfter heating for approximately 6 hours the mixture
  4. 4
    Températureto cool to room temperature
  5. 5
    ExtractionThe resulting mixture was extracted with ethyl acetate (4×300 ml)
  6. 6
    ExtractionThe aqueous layer (pH 0.37) after the first extraction with ethyl acetate
  7. 7
    workup.ADDITIONwas lowered to pH 0.18 by the addition of concentrated HCl (approximately 2 ml)
  8. 8
    Lavagewashed with brine (100 ml)
  9. 9
    SéchageAfter drying over anhydrous magnesium sulfate
  10. 10
    Autrethe solvent was removed at reduced pressure

Mode opératoire

A 500 ml three-necked flask was charged with dichloro-(3-hydroxy-adamantan-1-yl)-acetic acid (Formula IX) (38.67 g, 138.5 mmol). To this material was added water (160 ml) and 1 N NaOH (138 ml, 138 mmol; 1 N NaOH was used to generate the sodium salt of dichloro-(3-hydroxy-adamantan-1-yl)-acetic acid to avoid foaming problems which would occur with solid NaHCO3) to give a hazy solution. To this solution was added solid NaHCO3 (29.10 grams, 346 mmol, 2.50 equivalents). After the NaHCO3 was added the reaction mixture became a suspension as the sodium salt of dichloro-(3-hydroxy-adamantan-1-yl)-acetic acid was forced from solution. The reaction vessel was fitted with a reflux condenser/argon inlet and heated to approximately 80° C. After heating for approximately 6 hours the mixture was allowed to cool to room temperature. The reaction mixture (pH 7.22) was carefully acidified (CO2 evolution) to pH 0.15 by the addition of concentrated HCl (32 ml required). The resulting mixture was extracted with ethyl acetate (4×300 ml). The aqueous layer (pH 0.37) after the first extraction with ethyl acetate was lowered to pH 0.18 by the addition of concentrated HCl (approximately 2 ml). The ethyl acetate fractions were combined and washed with brine (100 ml). After drying over anhydrous magnesium sulfate, the solvent was removed at reduced pressure to give 3-hydroxy-<a-oxotricyclo[3.3.1.13,7]decane-1-acetic acid (Formula II) as a colorless granular solid: 30.77 gram (99%).

Source

DOI: 10.6084/m9.figshare.5104873.v1Brevet: US07420079B2uspto-grants-2008_09