Supramolecular control of reactivity and catalysis - effective molarities of recognition-mediated bimolecular reactions

Reactivity data relating to bimolecular reactions of compounds featuring complementary recognition sites are critically surveyed and discussed in terms of effective molarity (EM) as an absolute measure of the efficiency of the intracomplex reactions. Comparison of experimentally determined EM values with idealized values estimated for strain-free cyclizations on the basis of the number of internal rotors in the linker allowed quantification of the penalties of imperfect design in terms of entropy and strain.