反应详情

A solution (2.86 ml.) of methyl magnesium iodide in diethyl ether [prepared, in the manner well known in the art, from methyl iodide (6 g.), magnesium (1.07 g.) and diethyl ether (20 ml.)] was added dropwise to a stirred solution of 6-(7-trimethylsilyloxyheptyl)-7-(3-oxooct-1-enyl)-1,4-dioxaspiro[4,4]nonane (2.1 g.) in diethyl ether (80 ml.) at room temperature. The mixture was stirred for 30 minutes and a further quantity (1.09 ml.) of the solution of methyl magnesium iodide in diethyl ether was then added dropwise. The mixture was stirred for a further 30 minutes and then added to saturated aqueous ammonium chloride solution (250 ml.) at 0° C. and stirred for 15 minutes. The ether layer was separated and the aqueous layer extracted with diethyl ether. The combined ether layers were concentrated in vacuo to give crude 7-(3-hydroxy-3-methyloct-1-enyl)-6-(7-trimethylsilyloxyheptyl)-1,4-dioxaspiro[4,4]nonane (1.9 g.), ν max 845 cm-1, 1250 cm-1, 3400 cm-1, pure enough to use in the next stage.

1. stirringThe mixture was stirred for a further 30 minutes
2. stirringstirred for 15 minutes
3. customThe ether layer was separated
4. extractionthe aqueous layer extracted with diethyl ether
5. concentrationThe combined ether layers were concentrated in vacuo