(R)-(2-Iodo-1-methyl-ethyl)-carbamic acid benzyl ester → (R)-(1-Methyl-pent-4-enyl)-carbamic acid benzyl ester

HRID 229822Notes

Reaction equation

HRID 229822 reaction equation
[CH2:1]([Mg]Cl)[CH:2]=[CH2:3].[CH2:6]([O:13][C:14](=[O:20])[NH:15][C@H:16]([CH3:19])[CH2:17]I)[C:7]1[CH:12]=[CH:11][CH:10]=[CH:9][CH:8]=1>C1COCC1.CSC.[Cu]Br>[CH2:6]([O:13][C:14](=[O:20])[NH:15][C@H:16]([CH3:19])[CH2:17][CH2:3][CH:2]=[CH2:1])[C:7]1[CH:12]=[CH:11][CH:10]=[CH:9][CH:8]=1

Participants

5

Reactant 2

HCID 11631115(R)-(2-Iodo-1-methyl-ethyl)-carbamic acid benzyl esterHCID 178418473HCID 178418473, compound

Product 1

HCID 11107239(R)-(1-Methyl-pent-4-enyl)-carbamic acid benzyl ester

Reagents, catalysts & solvents 2

HCID 2724234Bromo(thiobis(methane))copperCatalystHCID 8028TetrahydrofuranSolvent2×

Conditions

Temperature
-78 °C

Procedure

Copper (I) bromide-dimethyl sulfide (1.93 g, 9.4 mmol) was dissolved in distilled THF (24 ml), then was cooled to −78 degrees C. A solution of allyl magnesium chloride (9.4 ml, 2M in THF, Aldrich) was added dropwise, then the solution was stirred for 30 minutes. ((R)-2-Iodo-1-methyl-ethyl)-carbamic acid benzyl ester (1.5 g, 4.7 mmol) in distilled THF (3 ml) was added dropwise, then the reaction was warmed to −40 degrees C. and was stirred for 2.5 h. The reaction mixture was quenched with aq. sat. NH4Cl (4 ml) at −40 degrees C., warmed to RT and the gray reaction mixture turned sky blue. THF was removed in vacuo. Then, Et2O was added and the reaction mixture was filtered to remove precipitated solids. The solids were washed with additional Et2O. The combined organics were extracted with 10% NH4OH (3×), then brine. The combined organics were dried with MgSO4, filtered, concentrated in vacuo, then filtered through a plug of silica gel washing with 20% EtOAc/hexanes (100 ml). The solution was concentrated in vacuo, then the resultant colorless oil was used in the next reaction without further purification (0.8 g, 73%).

Workup

  1. temperaturethe reaction was warmed to −40 degrees C
  2. stirringand was stirred for 2.5 h
  3. customThe reaction mixture was quenched with aq. sat. NH4Cl (4 ml) at −40 degrees C
  4. temperature, warmed to RT
  5. customTHF was removed in vacuo
  6. additionThen, Et2O was added
  7. filtrationthe reaction mixture was filtered
  8. customto remove
  9. customprecipitated solids
  10. washThe solids were washed with additional Et2O
  11. extractionThe combined organics were extracted with 10% NH4OH (3×)
  12. dry with materialThe combined organics were dried with MgSO4
  13. filtrationfiltered
  14. concentrationconcentrated in vacuo
  15. filtrationfiltered through a plug of silica gel washing with 20% EtOAc/hexanes (100 ml)
  16. concentrationThe solution was concentrated in vacuo
  17. customthe resultant colorless oil was used in the next reaction without further purification (0.8 g, 73%)

Sources & evidence

ORD record
ord-3d610c560c6a4b548b3b2689807d9552
Source dataset
uspto-grants-2009_07
Patent number
US07563784B2

Reaction notes

Loading…