| 摘要 |
PURPOSE:To readily obtain the titled compound which is a synthetic intermediate for medicines and agricultural chemicals, by reacting an aldehyde having >=2 hydroxyl groups as a raw material with a silyl enol ether in the presence of a Lewis acid catalyst. CONSTITUTION:An aldehyde having >=2 hydroxyl groups is reacted with a silyl enol ether in the presence of a Lewis acid in a solvent, particularly preferably dichloromethane at -50--100 deg.C, preferably -78 deg.C to afford the aimed compound. 1,3-Dioxolane and 1,3-dioxane compounds having formyl group at the 4-position are cited as the raw material aldehyde. Boron trifluoride.etherate is particularly useful as the Lewis acid. Furthermore, the silyl enol ether and Lewis acid are used in an amount of preferably 1.2-1.5 equiv. based on the raw material aldehyde. |
