in toluene Ce(O-i-Pr)4 is dissolved in toluene, soln. of n-Bu3SnCp is added, mixt. is heated at 65°C for 24 h (N2); mixt. is cooled to room temp., filtn., volatile components are removed under high vac., recrystn. at -78°C (pentane) or sublimation at 70°C (10E-5 Torr); elem. anal.;

in dichloromethane room temp., 30 min.;