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

HRID 3003

Reaction equation

HRID 3003 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

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-a43f21651da24fe980f402c4a2514be5
Source dataset
uspto-grants-1998_03
Patent number
US05731434

Linked notes

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