CHELATION-CONTROLLED CYCLIZATION OF β-KETOESTER-SUBSTITUTED AND β-KETOAMIDE-SUBSTITUTED ALLYLSILANES.
The first examples of Lewis acid-catalyzed chelation-controlled cyclization reactions are reported.Titanium tetrachloride-initiated cyclization of β-ketoester and β-ketoamide-substituted allylsilanes proceeds in isolated yields of 65-88percent, providing