Polymer-supported dichlorotitanium dialkoxide was readily prepared from polystyrene-bound α-glycol and dichlorotitanium diisopropoxide. When we employed it as an immobilized Lewisacidcatalyst, several fundamental and important Lewis acid-catalyzed reactions proceeded smoothly with fair chemical yields.
Aldehydes undergo smooth nucleophilic addition with allyltributylstannane in the presence of CeCl3·7H2O in acetonitrile under extremely mild reaction conditions to afford the corresponding homoallylicalcohols in excellent yields with high chemoselectivity. This method is very useful especially for the allylation of aldehydes bearing acid sensitive functionalities such as TBDMS, THP ethers, acetonides