TEMPLATION IN THE FORMATION OF CARCEPLEXES

The formation of carceplexes and hemicarceplexes involves an assembly process whereby a molecular template is entrapped between two bowl-sha ped molecules. The process can be highly selective such that a million -fold range in template recognition has been realized. The relative te mplate abilities, or template ratios, for 34 molecules in forming carc eplex a guest is described. Species with one, two, and three bridges l inking the two ''bowls'' are reported and were used to delineate the g uest-determining step of the reaction. The effect of base and solvent on the reaction are also described, and a discussion of the reaction m echanism is presented.