5-(2-Nitroethenyl)-1,3-benzodioxole → Methyl 2-(4-hexenoyl)-4-nitro-3-(1,3-benzodioxole-5-yl)butyrate

HRID 496757

Reaction equation

HRID 496757 reaction equation
[O:1]=[C:2]([CH2:8][CH2:9][CH:10]=[CH:11][CH3:12])[CH2:3][C:4]([O:6][CH3:7])=[O:5].[N+:13]([CH:16]=[CH:17][C:18]1[CH:26]=[CH:25][C:21]2[O:22][CH2:23][O:24][C:20]=2[CH:19]=1)([O-:15])=[O:14].C(OCC)(=O)C.CCCCCC>C(O)(C)C.C1COCC1.C1CCN2C(=NCCC2)CC1>[C:2]([CH:3]([CH:17]([C:18]1[CH:26]=[CH:25][C:21]2[O:22][CH2:23][O:24][C:20]=2[CH:19]=1)[CH2:16][N+:13]([O-:15])=[O:14])[C:4]([O:6][CH3:7])=[O:5])(=[O:1])[CH2:8][CH2:9][CH:10]=[CH:11][CH3:12]

Participants

7

Reactant 3

HCID 949455-(2-Nitroethenyl)-1,3-benzodioxoleHCID 51284636-Octenoic acid,3-oxo-, methyl esterHCID 21226206Ethyl acetate hexane

Product 1

HCID 53959667Methyl 2-(4-hexenoyl)-4-nitro-3-(1,3-benzodioxole-5-yl)butyrateYield 82%

Reagents, catalysts & solvents 3

HCID 811841,8-Diazabicyclo(5.4.0)undec-7-eneCatalystHCID 3776IsopropanolSolventHCID 8028TetrahydrofuranSolvent

Procedure

A solution of methyl 3-oxo-6-octenoate (502 mg, 2.95 mmol) in 10 mL of isopropanol was added to a solution of 5-(2-nitrovinyl)-1,3-benzodioxole (712 mg, 3.69 mmol) in 10 mL THF, then DBU (22 μL, 0.15 mmol) was added. The resulting reddish solution was stirred at room temperature for 20 minutes. TLC (ethyl acetate-hexane, 1:3) indicated complete consumption of ketoester. The solution was concentrated in vacuo and flash chromatographed on silica gel eluting with 18% ethyl acetate in hexane to produce 879 mg (2.42 mmol, 82%) of the title compound as a mixture of diastereomers in a 1:1 ratio. 1H NMR (CDCl3, 300 MHz) δ 1.55-1.66 (m, 3H), 2.02-2.17 (br m, 1H), 2.20-2.37 (m, 1.5H), 2.49-2.76 (m, 1.5H), 3.57 (s, 1.5H), 3.74 (s, 1.5H), 3.97 (d, J=7.5H, 0.5H) and 4.05 (d, J=8 Hz, 0.5H), 4.10-4.20 (m, 1H), 4.68-4.82 (m, 2H), 5.06-5.52 (m, 2H), 5.95 (2s, 2H), 6.65 (m, 1H), 6.68 (br s, 1H), 6.75 (d, 7.5 Hz, 1H). MS (DCl/NH3) m/e 381 (M+NH4)+. Anal calcd for C18H21NO7: C, 59.50; H, 5.82; N, 3.85. Found: C, 59.32; H, 5.71; N, 3.72.

Workup

  1. customconsumption of ketoester
  2. concentrationThe solution was concentrated in vacuo and flash
  3. customchromatographed on silica gel eluting with 18% ethyl acetate in hexane

Sources & evidence

ORD record
ord-9100f31f497b4e8ea90511e88b921734
Source dataset
uspto-grants-2005_09
Patent number
US06946481B1

Linked notes

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