反应详情

To a solution of lithium hexamethyldisilazide in tetrahydrofuran (20 ml, 5.0 mmol, 0.25M) was dropwise added with stirring on an oil bath at 55° C. under argon atmosphere a solution of 15-chloro-3-(1-methylethyl)-6,10,14-trimethyl-2-trimethylsiloxy-3,5,9,13-pentadecatetraenenitrile (378 mg, 0.895 mmol) in tetrahydrofuran (15 ml) in 50 minutes. The resultant mixture was stirred at this temperature for 20 minutes and poured into a mixture of saturated brine (30 ml)-hexane (20 ml) containing ice (50 g) for stopping the reaction. The organic layer was separated, and the aqueous layer was extracted with hexane-ether (5:1, 30 ml). The extract was dried over sodium sulfate and concentrated under reduced pressure. The resultant residue was chromatographed on a silica gel column to give 2-(1-methylethyl)-5,9,13-trimethyl-1-trimethylsiloxy-2,4,8,12-cyclotetradecatetraen-1-carbonitrile (H) (288 mg, 83%) and 2-(1-methylethyl)-5,9,13-trimethyl-2,4,8,12-cyclotetradecatetraen-1-one (42.9 mg, 0.11 mmol, 16%).

1. customthe reaction
2. customThe organic layer was separated
3. extractionthe aqueous layer was extracted with hexane-ether (5:1, 30 ml)
4. dry with materialThe extract was dried over sodium sulfate
5. concentrationconcentrated under reduced pressure
6. customThe resultant residue was chromatographed on a silica gel column