반응 #70666

ord-2d34fa7a753641baae9a11652494d32c

반응 조건

온도
-20°CELSIUS
상세 조건
See reaction.notes.procedure_details.

후처리

  1. 1
    기타To a clean and dry 2000 ml round bottom flask
  2. 2
    기타equipped with a 500 ml addition funnel
  3. 3
    기타The reaction vessel was placed into a dry ice/acetone bath until a temperature of <−65°
  4. 4
    workup.ADDITIONadded dropwise to the reaction
  5. 5
    기타to rise above −65° C
  6. 6
    workup.ADDITIONaddition
  7. 7
    workup.STIRRINGto stir for a period of 30 minutes
  8. 8
    기타The vessel was then removed from the dry ice/acetone bath
  9. 9
    기타was then again placed into the dry ice/acetone bath until a temperature of <−65°
  10. 10
    온도maintaining the current temperature
  11. 11
    workup.STIRRINGto stir for 30 minutes at this temperature
  12. 12
    workup.ADDITIONaddition
  13. 13
    온도The reaction was slowly warmed to room temperature over the following 12 hours
  14. 14
    온도After warming
  15. 15
    기타the reaction was quenched by the addition of isopropanol (20.0 ml) via syringe

실험 절차

To a clean and dry 2000 ml round bottom flask equipped with a 500 ml addition funnel, low temperature thermometer and magnetic stir bar was transferred anhydrous tetrahydrofuran (800.0 ml) under nitrogen. 2-(3-bromophenyl)-1,3-dioxolane (33.0 ml, 0.2183 mol) was added to this flask by syringe. The reaction vessel was placed into a dry ice/acetone bath until a temperature of <−65° was achieved. The reaction mixture was then allowed to stir for 45 minutes at a stirring speed of 550 rpm in order to verify the integrity of the stirring apparatus at this temperature. Tert-butyllithium solution (257.0 ml, 0.4690 mol) was transferred to the addition funnel by cannula, then added dropwise to the reaction never allowing the temperature to rise above −65° C. Following addition, the reaction was allowed to stir for a period of 30 minutes. The vessel was then removed from the dry ice/acetone bath and allowed to warm to a temperature of −20° C. The vessel was then again placed into the dry ice/acetone bath until a temperature of <−65° was achieved. 1,4-dibromobutane (103.5 ml, 0.8740 mol) was added to the reaction dropwise via syringe, maintaining the current temperature. The reaction was allowed to stir for 30 minutes at this temperature following addition. The reaction was slowly warmed to room temperature over the following 12 hours. After warming, the reaction was quenched by the addition of isopropanol (20.0 ml) via syringe.

출처

DOI: 10.6084/m9.figshare.5104873.v1특허: US08535974B2uspto-grants-2013_09