反应详情

温度

160 °C

To a solution of the relevant 2-hydroxy-spiro[5.5]undecan-2,7-diene-3-carboxylic acid methyl ester isomer (9) or (9′) (19.0 g, 85.0 mmol) in DMSO (66 mL) was added NaCl (5.5 g, 93.5 mmol) and H2O (4.6 mL, 255 mmol). The reaction mixture was heated at 160° C. for 6 hours then cooled and poured into H2O (100 mL). The aqueous layer was extracted with Et2O (5×) and the combined organic layers dried over anhydrous MgSO4. The solvent was removed in vacuo and the resulting residue purified over silica (n-pentane/Et2O, 95:5) to afford 13.3 g (95% yield) of the desired product as a colorless oil which was characterized as follows:

1. temperaturethen cooled
2. extractionThe aqueous layer was extracted with Et2O (5×)
3. dry with materialthe combined organic layers dried over anhydrous MgSO4
4. customThe solvent was removed in vacuo
5. customthe resulting residue purified over silica (n-pentane/Et2O, 95:5)