Silica gel-catalyzed cyclizations of mixed ketene acetals
作者:Dieter Schinzer、Markus Kalesse、Jazid Kabbara
DOI:10.1016/s0040-4039(00)80726-1
日期:1988.1
Mixed ketene acetals of type undergo smooth cyclization upon treatment with silica gel yielding diastereoselectively bicyclo[2.2.2]octanones of type . Alternatively, the same result was obtained by exposure of the substrates to TiCl4 at low temperature.