Acetic Acid → 2-Cyano-3-propyl-hex-2-enoic acid benzyl ester

HRID 1796827Notes

Reaction equation

HRID 1796827 reaction equation
[CH3:1][CH2:2][CH2:3][C:4](=O)[CH2:5][CH2:6][CH3:7].[C:9]([CH2:11][C:12]([O:14][CH2:15][C:16]1[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=1)=[O:13])#[N:10].C(O)(=O)C.N1CCCCC1>>[CH2:15]([O:14][C:12](=[O:13])[C:11]([C:9]#[N:10])=[C:4]([CH2:5][CH2:6][CH3:7])[CH2:3][CH2:2][CH3:1])[C:16]1[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=1

Participants

5

Reactant 4

HCID 176Acetic AcidHCID 8082PiperidineHCID 312464-HeptanoneHCID 560818Benzyl 2-cyanoacetate

Product 1

HCID 114257292-Cyano-3-propyl-hex-2-enoic acid benzyl esterYield 27%

Procedure

To a mixture of 4-heptanone (2.0 mL, 14.3 mmol) and benzyl cyanoacetate (2.51 g, 14.3 mmol) at 0° C. was added acetic acid (0.08 mL, 1.43 mmol), then piperidine (0.14 mL, 1.43 mmol) dropwise. The ice bath was removed, and stirring continued for 10 min. Additional acetic acid (0.08 mL) and piperidine (0.14 mL) were added, followed by the additional of oven-dried 4A molecular sieves such that stirring was not impeded. The mixture was stirred for 1 h, then partitioned between EtOAc and sat. sodium bicarbonate (NaHCO3) (aq). The phases were separated, and the organic phase washed with brine, dried (MgSO4), and concentrated to provide 1.03 g (27%) of 2-cyano-3-propyl-hex-2-enoic acid benzyl ester as a colorless oil. 1H NMR (CDCl3) δ 7.35 (m, 5H), 5.24 (s, 2H), 2.71 (m, 2H), 2.52 (m, 2H), 1.60 (m, 2H), 1.49 (m, 2H), 1.00 (t, J=7.3 Hz, 3H), 0.95 (t, J=7.3 Hz, 3H). 13C NMR δ 182.46, 161.72, 135.37, 128.83, 128.58, 128.21, 115.87, 104.77, 67.26, 40.77, 35.80, 22.36, 21.86, 14.54, 14.32. LRMS: m/z 272.1 (M+1). IR (neat) 2223, 1729 cm−1. Anal. Calcd for C17H21NO2: C, 75.25; H, 7.80; N, 5.16. Found: C, 75.44; H, 7.80; N, 5.22.

Workup

  1. customThe ice bath was removed
  2. additionAdditional acetic acid (0.08 mL) and piperidine (0.14 mL) were added
  3. dry with materialof oven-dried 4A molecular sieves such
  4. stirringthat stirring
  5. stirringThe mixture was stirred for 1 h
  6. custompartitioned between EtOAc and sat. sodium bicarbonate (NaHCO3) (aq)
  7. customThe phases were separated
  8. washthe organic phase washed with brine
  9. dry with materialdried (MgSO4)
  10. concentrationconcentrated

Sources & evidence

ORD record
ord-a0708fff74ee49779dc5a6a7ac17ade4
Source dataset
uspto-grants-2006_04
Patent number
US07030267B2

Reaction notes

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