Cyclic and Macrocyclic Organic Compounds - a Personal Review in Honor of Professor Leopold Ružička
; Sveučilište u Aachenu, Aachen, Njemačka
Ružička opened the field of cyclic molecules such as cyclic terpenes and cyclic ketones with up to 17 ring atoms. This work until now was extended in many directions such as cyclic paraffins, crown ethers and cryptands and cyclic ester amides. Cyclic molecules are formed upon electron transfer and intramolecular association of polymers with two active ends and they are synthesized by directed cyclization of bifunctional macromolecules. In the course of step growth polymerization and ring opening polymerization, ring chain equilibria may be established; the larger the monomer unit the easier is the separation of pure oligomers such as the heptamer of cyclododecene
with 84 carbon atoms in the ring. Still many questions remain open, in particular whether there are macrocyclic catenanes in commercial polycondensates.
Posjeta: 2.753 *