The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
The highly diastereoselective Mukaiyama-Michael reaction has been designed. Suppression of an electron-transfer process is crucial for this purpose and the following conditions should be satisfied. (1) TiCl 4 is employed as a Lewis acid. (2) Ketene silyl acetals have bulky siloxy and/or alkoxy group(s). (3) α-Enones have a bulky acyl group. The excellent syn-selectivity up to a 99:1 ratio is attained under these conditions. The selectivity is reversed to theanti -preference upon decreasing the size of the alkoxy group.