反应详情

A stirred solution of the acetal (1.0 g, 4.37 mmol) of Description 1 in dry tetrahydrofuran (50 ml), under argon, was cooled to -80° and treated with a 1.6 M solution of n-butyllithium in hexane (2.73 ml, 4.37 mmol). The resulting yellow solution was stirred at -80° for 0.5 hours. A solution of redistilled benzaldehyde (0.44 ml, 4.37 mmol) in dry tetrahydofuran (5 ml) was added over 2 minutes and the solution left to stir for 1 hour. The reaction mixture was warmed to room temperature over the next hour and then diluted with ethyl acetate and washed with water. The organic layer was dried (MgSO4) and evaporated to afford an oil which was chromatographed on silica gel. Elution with ethyl acetate/hexane (1:2) gave the desired product as a colourless oil (0.57 g, 51%). δH (CDCl3) 2.23 (1H, d, J 3.5 Hz), 4.1 (4H, m), 5.80 (1H, s), 5.87 (1H, d, J 3.5 Hz), 7.2-7.6 (9H) ppm. EIMS M+ 256.

1. waitthe solution left
2. stirringto stir for 1 hour
3. washwashed with water
4. dry with materialThe organic layer was dried (MgSO4)
5. customevaporated
6. customto afford an oil which
7. customwas chromatographed on silica gel
8. washElution with ethyl acetate/hexane (1:2)