反应详情

温度

138 °C

A mixture of (S)-2-(4-t-butyldimethylsilyloxy-1,3-dihydro-6-ethyl-7-methyl-3-oxoisobenzofuran-5-yl)-1-cyclopentenyl-1-hydroxyethane (2.8 g), pivalic acid (0.1 g) and triethyl orthoacetate (125 ml) was heated to 138° C. After 2.5 hours, more pivalic acid (65 mg) was added and the reaction was continued 1 hour more. The reaction mixture was cooled, the excess triethyl orthoacetate removed in vacuo, and the residue chromatographed on silica gel (20% ethyl acetate/hexane) to give ethyl (S)(E)-2-{2-[2-(4-t-butyldimethylsilyloxy-1,3-dihydro-6-ethyl-7-methyl-3-oxoisobenzofuran-5-yl)ethylidene]cyclopent-1-yl}acetate.

1. waitthe reaction was continued 1 hour
2. temperatureThe reaction mixture was cooled
3. customthe excess triethyl orthoacetate removed in vacuo
4. customthe residue chromatographed on silica gel (20% ethyl acetate/hexane)