p-Toluenesulfonic acid → Methyl 1-(spiro[benzo[d][1,3]dioxole-2,1'-cyclobutane]-5-yl)cyclopropanecarboxylate

HRID 1847371Notes

Reaction equation

HRID 1847371 reaction equation
[CH3:1][O:2][C:3]([C:5]1([C:8]2[CH:13]=[CH:12][C:11]([OH:14])=[C:10]([OH:15])[CH:9]=2)[CH2:7][CH2:6]1)=[O:4].CC1C=[CH:19][C:20](S(O)(=O)=O)=[CH:21][CH:22]=1.C1(=O)CCC1>C1(C)C=CC=CC=1>[C:19]12([O:14][C:11]3[CH:12]=[CH:13][C:8]([C:5]4([C:3]([O:2][CH3:1])=[O:4])[CH2:7][CH2:6]4)=[CH:9][C:10]=3[O:15]1)[CH2:20][CH2:21][CH2:22]2

Participants

5

Procedure

To a solution of 1-(3,4-dihydroxy-phenyl)-cyclopropanecarboxylic methyl ester (1.0 g, 4.8 mmol) in toluene (30 mL) was added TsOH (0.10 g, 0.50 mmol) and cyclobutanone (0.70 g, 10 mmol). The reaction mixture was heated at reflux for 2 h before being concentrated under vacuum. The residue was purified by chromatography on silica gel (petroleum ether/ethyl acetate 15:1) to give methyl 1-(spiro[benzo[d][1,3]dioxole-2,1′-cyclobutane]-5-yl)cyclopropanecarboxylate (0.6 g, 50%). 1H NMR (CDCl3 300 MHz) δ 6.78-6.65 (m, 3H), 3.62 (s, 3H), 2.64-2.58 (m, 4H), 1.89-1.78 (m, 2H), 1.56-1.54 (m, 2H), 1.53-1.12 (m, 2H).

Workup

  1. temperatureThe reaction mixture was heated
  2. temperatureat reflux for 2 h
  3. concentrationbefore being concentrated under vacuum
  4. customThe residue was purified by chromatography on silica gel (petroleum ether/ethyl acetate 15:1)

Sources & evidence

ORD record
ord-b44b1b6d48a44dc8ae1df5352927cca8
Source dataset
uspto-grants-2015_02
Patent number
US08952050B2

Reaction notes

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