C([O:3][CH3:4])=O.[CH3:5][C:6]1([C:13](=O)[CH3:14])[CH2:9][C:8]2([CH2:12][CH2:11][CH2:10]2)[CH2:7]1.[H-].[Na+]>CCOCC.CO>[CH3:5][C:6]1([CH:13]([CH:14]=[CH:4][OH:3])[CH2:14][CH2:13][CH2:6][CH2:7][CH2:8][CH3:9])[CH2:9][C:8]2([CH2:12][CH2:11][CH2:10]2)[CH2:7]1A solution of 7.8 g (130.0 mmol) methyl formate and 4.91 g (32.4 mmol) of 2-methyl-2-acetylspiro[3.3]heptane in 8.0 ml of dry ether was dropped into a slurry of 1.2 g of sodium hydride in 180 ml of ether. A few drops of MeOH were added and the reaction mixture stirred for 1.5 hr at 25° C. The reaction mixture was cooled to -10° C and the reaction quenched by slow addition of water. The layers were separated and the aqueous layer extracted twice with ether. The combined organic extracts were washed with water and 1 N NaOH. The combined aqueous layers were acidified with 6 N HCl and extracted with ether. The ether extracts were washed with brine, then dried (MgSO4), filtered and evaporated in vacuo to yield 4.0 g of (2-methylspiro[3.3]hept-2-yl)(2-hydroxyvinyl)heptane as a yellow oil (69.5%).
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