反应详情

A mixture of 32.0 g of 1-[2,6,6-trimethyl-3-(trimethylsiloxy)-1,3-cyclohexadien-1-yl]-3-methoxy-3-methyl-1,4-pentadiene, 10.0 g of sodium hydrogen carbonate, 10.0 g of magnesium sulphate trihydrate and 500 ml of diethyl ether was stirred well at 2°-5° C., then treated dropwise with 26.45 g of 40% peracetic acid and left to warm to room temperature. The mixture was subsequently cooled to 0° C., treated dropwise with 90 ml of a mixture of methanol and 1N hydrochloric acid (vol. 1:1) and extracted with diethyl ether. The organic phase was washed twice with cold semi-concentrated sodium pyrosulphite solution, once with ice-water, twice with ice-water to which had been added a small amount of saturated sodium hydrogen carbonate solution and a further twice with ice-water. After drying over sodium sulphate and concentration under a water-jet vacuum at 35° C., there were obtained 26.4 g of crude 1-(4-hydroxy-3-oxo-2,6,6-trimethyl-1-cyclohexen-1-yl)- 3-methoxy-3-methyl-1,4-pentadiene (purity 91.5%) which still contained 7.07% of 1-(3-oxo-2,6,6-trimethyl-1-cyclohexen-1-yl)-3-methoxy-3-methyl-1,4-pentadiene.

1. waitleft
2. temperatureThe mixture was subsequently cooled to 0° C.
3. extractionextracted with diethyl ether
4. washThe organic phase was washed twice with cold semi-concentrated sodium pyrosulphite solution, once with ice-water, twice with ice-water to which
5. additionhad been added a small amount of saturated sodium hydrogen carbonate solution
6. dry with materialAfter drying over sodium sulphate and concentration under a water-jet vacuum at 35° C.