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

HRID 54574

Reaction equation

HRID 54574 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 (DCI/NH3) m/e 381 (M+NH4)+.

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-9e5b71029b4a48c9ad22e05383a47ff9
Source dataset
uspto-grants-1997_04
Patent number
US05622971

Linked notes

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