Reaction #62691

ord-456b9033347340a1acbd3539a4ba158d

Solvents

Conditions

Detailed conditions
See reaction.notes.procedure_details.

Workup

  1. 1
    Temperaturecooled to 5° C
  2. 2
    workup.STIRRINGthe solution stirred for 1 hour at room temperature
  3. 3
    WashThe solution was then washed with water
  4. 4
    Dryingthe organic layer dried over sodium sulfate
  5. 5
    Otherevaporated under reduced pressure
  6. 6
    OtherThe product was recrystallized from ethyl acetate

Procedure

A solution of 2,6-dimethyl-3-carbomethoxy-4-(3-nitrophenyl)-5-carboxy-1,4-dihydropyridine (107 g, 0.32 mol) in CH2Cl2 (520 mL) and DMF (100 mL) was cooled to 0° C. and thionyl chloride (28 mL, 0.39 mol) slowly added. The mixture was stirred at room temperature for 1 hour, then cooled to 5° C. Distilled 3-bromopropanol (35 mL, 3.9 mol) was slowly added, and the solution stirred for 1 hour at room temperature. The solution was then washed with water and the organic layer dried over sodium sulfate and evaporated under reduced pressure. The product was recrystallized from ethyl acetate to yield 2,6-dimethyl-3-carbomethoxy-4-(3-nitrophenyl)-5-(3-bromopropoxycarbonyl)-1,4-dihydropyridine (12, mp=146° C.).

Source

DOI: 10.6084/m9.figshare.5104873.v1Patent: US04761420uspto-grants-1988_08