1,3-Nonadien-2-yl acetate → 3-Nonen-2-yl acetate

HRID 1419601Notes

Reaction equation

HRID 1419601 reaction equation
[C:1]([O:4][C:5]([CH:7]=[CH:8][CH2:9][CH2:10][CH2:11][CH2:12][CH3:13])=[CH2:6])(=[O:3])[CH3:2]>O1CCCC1.F[B-](F)(F)F.C1([Rh+]C2CCCCC=CC=2)CCCCC=CC=1>[C:1]([O:4][CH:5]([CH:7]=[CH:8][CH2:9][CH2:10][CH2:11][CH2:12][CH3:13])[CH3:6])(=[O:3])[CH3:2]

Participants

4

Reactant 1

HCID 545150541,3-Nonadien-2-yl acetate

Product 1

HCID 544463673-Nonen-2-yl acetateYield 106.5%

Reagents, catalysts & solvents 2

HCID 178420271HCID 178420271, compoundCatalystHCID 8028TetrahydrofuranSolvent

Procedure

Bis(cyclooctadienyl)rhodium tetrafluoroborate (10 mg; 0.005 mmol; 0.02 equiv) and R,R-1,2-bis(2,5-dimethylphospholano)benzene (6, R"=CH3 ; 9 mg; 0.03 mmol; 0.006 equiv) were combined in a pressure tube equipped with a magnetic stir bar under argon. The tube was evacuated and filled with argon five times, and then 2.5 mL of degassed tetrahydrofuran (THF) was added to afford a yellow-orange solution. 1,3-Nonadien-2-yl acetate (1a; 911 mg; 5 mmol) dissolved in 2.5 mL of degassed THF was then added. The reaction mixture was evacuated and filled with argon five times and then was evacuated and filled with hydrogen three times. The reaction mixture was placed under 30 psi of hydrogen and stirred at room temperature overnight, at which time hydrogen uptake had ceased. The vessel was vented and flushed with nitrogen, and the reaction mixture was concentrated to afford 981 mg of crude 3-nonen-2-yl acetate (2a) containing a small amount of the fully saturated analog. Analysis of this material by chiral GC and comparing to authentic racemate showed a 96:4 ratio of enantiomers (92% ee). Conversion to 2-nonanol (hydrolysis and hydrogenation) and comparison with authentic material indicated the (R) absolute configuration. Thus, the asymmetric hydrogenation of the present invention yielded the desired product having high optical purity. The spectra is shown below:

Workup

  1. customequipped with a magnetic stir bar under argon
  2. customThe tube was evacuated
  3. additionfilled with argon five times
  4. addition2.5 mL of degassed tetrahydrofuran (THF) was added
  5. customto afford a yellow-orange solution
  6. additionwas then added
  7. customThe reaction mixture was evacuated
  8. additionfilled with argon five times
  9. customwas evacuated
  10. additionfilled with hydrogen three times
  11. customflushed with nitrogen
  12. concentrationthe reaction mixture was concentrated

Sources & evidence

ORD record
ord-9f4e7ba8563d4a94b4206980252bb270
Source dataset
uspto-grants-1999_03
Patent number
US05886214

Reaction notes

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