References
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- Strowell , J. C. 1984 . Chem. Rev. , 84 : 409 For a review on three carbon homologating agents see:
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- General procedure for the addition of Grignard reagents to 3: A solution of the appropriate vinylic selenide (4 mmol) in THF (5 ml) was added dropwise to a solution of the Grignard reagent (5.2 mmol) in THF (10 ml). The mixture was stirred for 5 min at 0°C and then was allowed to warm to room temperature. After 1h stirring the mixture was treated with saturated solution of ammonium chloride and extracted with petroleum either. The organic layer was dried with potassium carbonate and the solvent was evaporated to give a yellow oil with the yields shown in Table 1
- General procedure of the addition of n-butyllithium to 3: n-Butyllithium (2.08 ml, 5 mmol of a 2.4 M solution in hexane) was added to a solution of 3 (5 mmol) in THF (5 ml) at -78°C under nitrogen. After 5 min of stirring the mixture was allowed to warm to room temperature and stirred for 30 min. Then it was dilluted with ethl ether (30 ml) and washed with saturated solution of ammonium chloride and brine. The organic layer was dried with potassium carbonate and evaporated to give a yellow oil will the yields shown in Table 1
- General procedure for the hydrolysis of 5: A solution of 5 (0.5 g) in methylene dichloride (6 ml) was added dropwise to a suspension of silica gel (70–230 Mesh, 3 g) in methylene dichloride (6 ml) and 30% H2SO4 (0.45 ml). After 24 h of stirring at room temperature the mixture was filtered through a sinterized funnel. The filtrate was washed with a saturated solution of sodium bicarbonate, dried with potassium carbonate and evaporated. The residue was purified by column chromatography on silica gel eluting with petroleum ether/ethyl acetate (9:1)