Tetrahydrofuran → 6'-Bromospiro[cyclobutane-1,2'-inden]-1'(3'H)-one

関与物質

反応条件

反応手順

A dried flask charged with 1-(4-bromo-2-iodobenzyl)cyclobutanecarbonitrile (Intermediate 37, 2.60 g, 6.91 mmol), was dissolved in dry THF (100 mL) under an argon atmosphere. The resulting mixture was cooled to −78° C. and then was tert-butyllithium (1.7 M in pentane, 8.13 mL, 13.83 mmol), added dropwise. The reaction was stirred for 1.5 h at −78° C. and then the reaction was quenched with MeOH (0.5 mL), followed by aq. hydrochloric acid (2M, 10 mL). The resulting solution was concentrated to remove the organic solvent and then partitioned between DCM and water. The organic phase was dried over MgSO4 and concentrated to give a crude product which was purified by flash chromatography (eluent: heptane/EtOAc20:1-15:1-10:1) to afford the title compound (1.1 g, 63% yield): 1H NMR (500 MHz, CDCl3) δ ppm 1.97-2.13 (m, 3 H), 2.13-2.24 (m, 1 H), 2.45-2.60 (m, 2 H), 3.24 (s, 2 H), 7.31 (d, 1 H), 7.67 (dd, 1 H), 7.88 (d, 1 H); GC MS (EI) m/z 250 M+.

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