Formic Acid → (S)-4-bromo-7-fluoro-2,3-dihydro-1H-inden-1-ol

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

Triethylamine (26.2 mL, 187 mmol) is dissolved in dichloromethane (100 mL) and cooled to 0° C. then formic acid (7.96 mL, 211 mmol) is added dropwise with cooling. 4-Bromo-7-fluoro-indan-1-one (European patent EP2042480, 13.8 g, 60 mmol) is added and the mixture degassed with a flow of argon. Chloro([1S,2S)-(+2-amino-1,2-diphenylethyl](4-toluenesulfonyl)amido)(mesitylene)ruthenium(II) complex (375 mg, 0.6 mmol) is added and the mixture is stirred overnight at room temperature. Water is added, the mixture shaken and the phases separated. The organic phase is dried and concentrated under vacuum. The residue is purified by flash chromatography (0-20% ethyl acetate in cyclohexane) to give the title compound (Yield 13.1 g). GC (METHOD 1): tR=9.35 min; Mass spectrum (EI+): m/z=229, 231 [M]+, e.e. 100% by chiral HPLC (Column: Daicel Chiralcel OJ-H, 4.6×250 mm, 5 μm Mobile phase: hexane:ethanol 95:5, 1 mL/min, 25° C.) tR=9.87 min.

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