ABSTRACT
In a historical perspective, as pointed out by J.-M. Lehn (1992), supramolecular chemistry originated from Paul Ehrlich’s receptor idea, Alfred Werner’s coordination chemistry, and Emil Fischer’s lock-and-key image. It was only in the 1970s, however, that some fundamental concepts such as molecular recognition, pre-organization, self-assembly, etc., were introduced and supramolecular chemistry began to emerge as a discipline. The most authoritative and widely accepted definition of supramolecular chemistry is that given by J.-M Lehn, namely “the chemistry beyond the molecule, bearing on organized entities of higher complexity that result from the association of two or more chemical species held together by intermolecular forces. In more general terms, when the interaction energy between units is small compared to the other relevant energy parameters, a system can be considered a supramolecular species, regardless of the nature of the bonds that link the units.
