Triethyl phosphite → 2-(2-Cyclopentylethyl)-5-Phenyloxazole

HRID 863805Notes

Reaction equation

HRID 863805 reaction equation
[CH:1]1([CH2:6][CH2:7][C:8]([O:10][C:11]([C:16]2[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=2)=[CH:12][N:13]=[N+]=[N-])=O)[CH2:5][CH2:4][CH2:3][CH2:2]1.P(OCC)(OCC)OCC>C1CCCCC1>[CH:1]1([CH2:6][CH2:7][C:8]2[O:10][C:11]([C:16]3[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=3)=[CH:12][N:13]=2)[CH2:5][CH2:4][CH2:3][CH2:2]1

Participants

4

Reactant 2

HCID 31215Triethyl phosphiteHCID 539691652-Azido-1-Phenylvinyl 3-Cyclopentylpropionate

Product 1

HCID 194205152-(2-Cyclopentylethyl)-5-PhenyloxazoleYield 46.6%

Reagents, catalysts & solvents 1

HCID 8078CyclohexaneSolvent

Procedure

To a stirred solution of 2-azido-1-phenylvinyl 3-cyclopentylpropionate from Step A (4.0 g, 14 mmol) in dry cyclohexane (10 mL) was added triethyl phosphite (12 g, 74 mmol) dropwise. After stirring at room temperature for 1 h, the mixture was heated at 90° C. in an oil bath under nitrogen for 6 h. The mixture was cooled and chromatographed on a silica gel column (eluent: 1:5 ethyl acetate:hexanes) to give 1.57 g (46.6%) of the title compound as a white solid: 1H NMR (400 MHz, CDCl3) δ7.59 (dt, 2H, J=2.0,8.2 Hz), 7.38 (dr, 2H, J=1.4, 8.0 Hz), 7.29 (tt, 1H, J=2.0, 8.0 Hz), 7.19 (s, 1H), 2.82 (t, 2H, 7.5 Hz), 1.89-1.75 (m, 5H), 1.61-1.47 (m, 4H), 1.11 (m, 2H).

Workup

  1. temperaturethe mixture was heated at 90° C. in an oil bath under nitrogen for 6 h
  2. temperatureThe mixture was cooled
  3. customchromatographed on a silica gel column (eluent: 1:5 ethyl acetate:hexanes)

Sources & evidence

ORD record
ord-1de7a786c2d44b50a3d9c232631e71f7
Source dataset
uspto-grants-1996_10
Patent number
US05561142

Reaction notes

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