Methanol → 2-(4-Methyl-1-oxo-1,3-dihydroisobenzofuran-5-yl)acetaldehyde

Reaction equation

[CH3:1][C:2]1[C:10]2[CH2:9][O:8][C:7](=[O:11])[C:6]=2[CH:5]=[CH:4][C:3]=1[CH2:12][CH:13]=C.CSC.C[OH:19]>>[CH3:1][C:2]1[C:10]2[CH2:9][O:8][C:7](=[O:11])[C:6]=2[CH:5]=[CH:4][C:3]=1[CH2:12][CH:13]=[O:19]

Participants

Reactant 3

HCID 887Methanol

HCID 1068Dimethyl Sulfide

HCID 666465364-methyl-5-prop-2-en-1-yl-2-benzofuran-1(3H)-one

Product 1

HCID 772312602-(4-Methyl-1-oxo-1,3-dihydroisobenzofuran-5-yl)acetaldehyde

Procedure

A solution of 4-methyl-5-prop-2-en-1-yl-2-benzofuran-1(3H)-one (220 mg, 1.2 mmol) in MeOH (20 mL) was cooled to −78° C. To this solution was bubbled ozone until the reaction turned blue. Nitrogen was bubbled through the reaction to drive off excess ozone, followed by addition of DMS (0.870 mL, 11.7 mmol). The reaction was allowed to warm up to RT. The solvents were removed under reduced pressure. The crude product was purified by flash chromatography to afford (4-methyl-1-oxo-1,3-dihydro-2-benzofuran-5-yl)acetaldehyde. 1H-NMR (500 MHz, CDCl3) δ ppm 9.78 (s, 1H), 7.75 (d, J=7.5 Hz, 1H), 7.34 (d, J=7.5 Hz, 1H), 5.27 (s, 2H), 3.90 (s, 2H), 2.23 (s, 3H).