Dichloromethane → 6-Hydroxy-2,3-dihydro-1H-indene-5-carbonitrile

Beteiligte Stoffe

Reaktionsschritte

To a stirred solution of Indan-5-ol (5.0 g, 32.3 mmol) in anhydrous dichloroethane (21.5 mL) was added, at 0° C., 1.0 M boron trichloride in dichloromethane (41.0 mL, 41.0 mmol, 1.2 eq), followed by methyl thiocyanate (2.43 mL, 35.5 mmol, 1.1 eq) and aluminum chloride (4.30 g, 2.3 mmol, 1.0 eq). The reaction mixture was stirred at room temperature for 2 d and then cooled to 0° C. To the dark brown reaction mixture was added 50% aqueous sodium hydroxide solution (100 mL) until pH=11. The resulting yellow biphasic layers were stirred at reflux for 3 h. The biphasic layers were separated, and the aqueous layer was adjusted to pH=1 with 50% aqueous hydrogen chloride solution at 0° C. The acidified aqueous mixture was extracted with ethyl acetate, and the combined organic layers were dried over sodium sulfate and concentrated at reduced pressure. Crystallization from ether-hexane afforded the cyanophenol as a white solid (3.02 g, 50.9%). 1H-NMR (DMSO-d6) δ 10.67 (s,1H), 7.36 (s, 1H), 6.84 (s,1H), 2.81 (t, J=7.5 Hz, 2H), 2.73 (t, J=7.5 Hz, 2H), 1.99 to 1.93 (m, 2H); Rf=0.23, 25% ethyl acetate-hexane.

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