O Si Si O O Si Si O Si Si O I II III ... Mes Si Mes F F Mes Si Mes F H Mes Si Mes F OH ... Mes Si Mes H H Mes Si Mes H OH Mes Si Mes HO OH ... Zeng-Rong Zhang,a James Y. Becker*a and Robert C. Westb a Department of Chemistry, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel. E-mail: becker@bgumail.bgu.ac.il b Department of Chemistry, University of Wisconsin, Madison, WI 53706, USA ... Received (in Cambridge, UK) 22nd October1998, ...
