Ethyl Acetate → Diphenylphosphine oxide

HRID 1929324Notes

Reaction equation

HRID 1929324 reaction equation
[PH3:1]=[O:2].[C:3]1([Li])[CH:8]=[CH:7][CH:6]=[CH:5][CH:4]=1.C(OCC)(=O)C.CC(O)C.[CH3:20][CH2:21][CH2:22][CH2:23][CH2:24][CH3:25]>C1COCC1>[PH3:1]=[O:2].[C:3]1([PH:1](=[O:2])[C:22]2[CH:21]=[CH:20][CH:25]=[CH:24][CH:23]=2)[CH:8]=[CH:7][CH:6]=[CH:5][CH:4]=1

Participants

7

Reactant 4

HCID 8857Ethyl AcetateHCID 21585144Isopropanol hexaneHCID 178506676HCID 178506676, compoundHCID 178527022HCID 178527022, compound

Product 2

HCID 254003Diphenylphosphine oxideYield 64%HCID 178527022HCID 178527022, compound

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent3×

Conditions

Temperature
-78 °C

Procedure

To a stirred solution of phosphine oxide 10 (45 mg, 77 μmol) in anhydrous THF (600 μl) a 1.5 M solution of phenyl lithium in THF (75 μl, 105 μmol) was added at −20° C. under argon. The mixture was stirred for 20 min. and then cooled to −78° C. A precooled solution of 9 (6 mg, 33 μmol) in anhydrous THF (200 μl) was added via cannula and the reaction mixture was stirred for 3 h at −78° C. After that the reaction mixture was stirred at 4° C. overnight. Then ethyl acetate was added and organic phase was washed with brine, dried over anhydrous Na2SO4 and concentrated under reduced pressure. The residue was purified on Waters silica gel Sep-Pack cartridge (hexane to 3% ethyl acetate/hexane) and then on HPLC (0.03% 2-propanol/hexane, 4 mL/min., Zorbax-silica 10×250 mm) to give 11.4 mg (21 mmol, 64% yield) of 11 at Rt=7.08 min. UV (hexane) λmax=242, 250, 261 nm; 1H NMR (400 MHz, CDCl3) δ 0.03 (3H, s), 0.04 (3H, s), 0.07 (3H, s), 0.08 (3H, s), 0.80 (3H, d, J=6.8 Hz), 0.86 (9H, s), 0.89 (9H, s), 2.18 (1H, dd, J=12.4 Hz, J=7.7 Hz), 2.86 (1H, br d, J=13.8 Hz), 4.42 (1H, m), 4.93 (1H, s), 4.96 (1H, s), 5.93 (1H, d, J=11.2 Hz), 6.20 (1H, d, J=11.2 Hz); 13C NMR (100 MHz, CDCl3) δ −5.1, −4.9, −4.8, 18.2, 18,2, 18.3, 21.6, 24.6, 25.8, 25.8, 27.8, 28.9, 29.8, 31.9, 38.7, 47.5, 50.7, 50.8, 52.7, 71:9, 72.3, 106.3, 113.7, 122.4, 132.9, 143.7, 153.0; MS (EI) m/z 544 (3, M+), 448 (9), 412 (36), 366 (14), 313 (11), 290 (100); exact mass calculated for C33H60O2Si2 544.4132, found 544.4131.

Workup

  1. stirringthe reaction mixture was stirred for 3 h at −78° C
  2. stirringAfter that the reaction mixture was stirred at 4° C. overnight
  3. washorganic phase was washed with brine
  4. dry with materialdried over anhydrous Na2SO4
  5. concentrationconcentrated under reduced pressure
  6. customThe residue was purified on Waters silica gel Sep-Pack cartridge (hexane to 3% ethyl acetate/hexane)

Sources & evidence

ORD record
ord-e7dead64c48b4f89af5572acb4f48480
Source dataset
uspto-grants-2012_05
Patent number
US08188064B2

Reaction notes

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