반응 #5376

ord-07d0a3d4d786447dba463b8c0927c013

반응 조건

온도
-6.25°CELSIUS
상세 조건
See reaction.notes.procedure_details.

후처리

  1. 1
    온도by cooling at ca. -5° C
  2. 2
    workup.STIRRINGunder stirring
  3. 3
    기타temperature below 5° C.
  4. 4
    온도under cooling with ice
  5. 5
    workup.STIRRINGstirring
  6. 6
    온도the reaction temperature was raised up to 45° C.
  7. 7
    온도maintained for 90 minutes
  8. 8
    기타After the reaction
  9. 9
    workup.ADDITIONwas added
  10. 10
    기타to precipitate a crystal
  11. 11
    여과The crystal was filtered
  12. 12
    세척washed with water
  13. 13
    기타by recrystallizing from a mixture solvent of acetone-methanol

실험 절차

Example Compound I-51 was synthesized through the following steps: ##STR88## 1.61 g (40.3 m mole) of sodium hydroxide was dissolved in 10.7 ml of water, followed by cooling at -7.5--5° C. on ice-common salt bath. To the solution, 0.66 ml (25.6 m mole) of bromic acid was added dropwise under stirring, followed by cooling at ca. -5° C. To the mixture solution, 4.2 ml of dioxane was added dropwise under stirring to prepare sodium hypobromite solution. In a 200 ml three-neck flask, 1.50 g (3.81 m mole) of (4-decyloxyphenyl)-5-acetylbenzooxazole synthesized in Example 3, 30 ml of dioxane and 2.5 ml of water were placed, followed by keeping inner temperature below 5° C. under cooling with ice and stirring. To the mixture solution, the above-mentioned sodium hypobromite solution was added dropwise, and the reaction temperature was raised up to 45° C. and maintained for 90 minutes. After the reaction, the reaction mixture was poured into 150 ml of water. To the resultant reaction mixture, 3.2 ml of chloric acid was added to show pH=1 to precipitate a crystal. The crystal was filtered and washed with water, followed by recrystallizing from a mixture solvent of acetone-methanol to obtain 1.13 g of 2-(4-decyloxyphenyl)-5-carboxybenzooxazole (Yield: 75.0%).

출처

DOI: 10.6084/m9.figshare.5104873.v1특허: US05244596uspto-grants-1993_09