Acylation of silylenol ethers 1 and 9 yield with 2-alkoxy-2-alkyl(or aryl)-1,3-dioxolanes 5 in a simple way by zinc dichloride-diethyl ether-catalysis regioselectively the α- and γ-protected dicarbonyl derivatives 6, 7, and 10. The enhanced reactivity of the cyclic orthoesters 5 in this reaction is discussed in comparison with acyclic reagents. The yield is influenced by steric effects at the reaction center.
|Translated title of the contribution||Silylenol ether functionalization, III. Regioselective acylation of trimethylsilylenol ethers with 2-alkoxy-1,3-dioxolanes. Synthesis of α- and γ-protected dicarbonyl compounds|
|Number of pages||9|
|Journal||Monatshefte für Chemie Chemical Monthly|
|State||Published - May 1 1984|
- Dicarbonyl compounds, α- and γ-protected
- Synthesis, with trimethylsilylenol ethers and cyclic ortho esters