(4-Hydroxy-2-(pyridin-3-yl)-1-oxa-9-azaspiro[5.5]undec-2-en-9-yl)(4-isopropoxy-3-methylphenyl)methanone → 4-Isopropoxy-3-methylbenzaldehyde

Participants

Reaction Steps

[8-hydroxy-10-(3-pyridyl)-11-oxa-3-azaspiro[5.5]undec-9-en-3-yl]-(4-isopropoxy-3-methyl-phenyl)methanone (1.20 g, 2.84 mmol) was dissolved in ethanol. Under nitrogen, palladium (90.7 mg, 0.09 mmol) (10 wt % on carbon, wet) was added. The reaction system was flushed with hydrogen gas, and the mixture was stirred under a balloon of hydrogen gas overnight. The reaction mixture was filtered through a pad of celite. The concentrated filtrate was purified by column chromatography (70-100% ethyl acetate/hexane) to provide cis-8-hydroxy-10-(3-pyridyl)-11-oxa-3-azaspiro[5.5]undecan-3-yl]-(4-isopropoxy-3-methyl-phenyl)methanone (520 mg) as a white foaming solid. 1H NMR (400 MHz, CDCl3) δ 8.65 (s, 1H), 8.57 (d, J=4.2 Hz, 1H), 7.80 (d, J=7.5 Hz, 1H), 7.37 (s, 1H), 7.19 (d, J=8.5 Hz, 2H), 6.80 (d, J=8.1 Hz, 1H), 4.65 (br s, 1H), 4.55 (dt, J=12.1, 6.0 Hz, 1H), 4.40 (br s, 1H), 4.17 (br s, 1H), 3.75-3.01 (m, 3H), 2.27-2.12 (m, 2H), 2.19 (s, 3H), 2.13-1.93 (m, 2H), 1.84-1.39 (m, 4H), 1.34 (d, J=6.0 Hz, 6H). ESI-MS m/z calc. 424.24, found 425.4 (M+1)+; Retention time: 1.13 minutes (3 min run).

Provenance & Evidence