Entry into the 16–24 membered new crownether/polyethermacrocyclic molecules and the post ring-closure functional derivatization/periphery modification of polyethermacrocyclic systems are reported. The synthesis of the epoxide, α-hydroxy ketone and olefinic functionality installed crownether/polyethermacrocyclic molecules was accomplished using the ring closing metathesis (RCM), epoxidation, oxidation