Ring-closing metathesis reaction-based synthesis of new classes of polyether macrocyclic systems

Abstract

Ring closing metathesis (RCM) reactions of suitable substrates having terminal olefins, which are assembled from various linkers and hydroxy benzaldehydes and syntheses of a wide range of 16–30 membered, new crown ether-type polyether, aza-polyether, bis aza-polyether macrocycles and dilactone moiety embedded polyether macrocycles (macrolides) are reported. After the ring-closure reaction, installation of different functional groups and functional group modification on the periphery of the synthesized polyether/crown ether macrocycles obtained in the RCM reactions are accomplished using the epoxidation, oxidation and catalytic hydrogenation-based synthetic transformations. Along this line, the syntheses of a variety of polyether macrocycles possessing epoxide or α-hydroxy ketone or 1,2-diol functionalities at the periphery have been shown. Furthermore, the synthesized α-hydroxy ketone functionality installed polyether macrocycles were subjected to the allylation and Reformatsky type reactions to obtain homoallyl alcohol moiety-based and lactone ring-appended polyether macrocycles.