Acetic Acid → [(S)-6-((R)-7-Fluoro-4-hydroxyindan-1-yloxy)-2,3-dihydrobenzofuran-3-yl]-acetic acid methyl ester

Participants

Reaction Conditions

Reaction Steps

4.41 g (8.72 mmol) {(S)-6-[(R)-7-fluoro-4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-indan-1-yloxy]-2,3-dihydrobenzofuran-3-yl}-acetic acid methyl ester is dissolved in 10 ml EtOH and 2.20 ml glacial acetic acid and 2.20 ml water are added. The funnel is rinsed with 7.50 ml EtOH. Then, 2.28 g (14.8 mmol) sodium perborate is added in portions at r.t. and the mixture is stirred. After complete addition, 1.40 ml water and 1.6 ml toluene is added. The organic phase is separated and 1.60 ml water is added. After cooling to 0° C., the 2-phasic mixture is seeded and stirring is continued. The precipitated product is filtered off, washed with cold toluene and dried. Yield: 2.86 g; Rf=0.22 (silica gel, PE/EtOAc=7/3); Mass spectrum (ESI): m/z=359 [M+H]+.

Provenance & Evidence