A new series of macrocyclic polyether‐diesler compounds (3‐12) have been prepared by treating various oligoethylene glyeols or mercaplans with oxalyl chloride. The compounds prepared were: 1,4,7,10,13‐pentaoxacyclopentadecane‐2,3‐dione (3), 1,4,7,1 3‐tetraoxa‐10‐thiacyclopenta‐decane‐2,3‐dione (4), 1,4,10‐lrioxa‐7,13‐dithiacyclopenladecane‐2,3‐dione (5), 1,4,7,10,13,16‐hexaoxacyclooctadecane‐2,3‐dione (6), 1,4,7,10,13, 16‐hexaoxacyclooctadecane‐2,3,11,12‐tetra‐one (7), 1,4,10,13‐tetraoxa‐7,16‐dithiacyclooctadecane‐2,3,11,12‐tetraone (8), 7,16‐dioxa‐1,4, 10,13‐letralhiacyclooctadecane‐2,3,11,12‐tctraone (9), 1,4,7,10,13,16‐hexathiacyclooctadecane‐2,3,11,12‐tetraone (10), 1,4,7,10,13,16,19‐heptaoxacyclohencicosane‐2,3‐dione (11), and 1,4,7, 10,13,16,19,22‐octaoxacyclolelracosane‐2,3,14,15‐letraone (12).