Synthesis of Macrocyclic Lactones Building on Double Calix[4]arenes

The macrocyclic lactones building on calix4]arenes 3a-b and double calix4]arenes 4a- h were synthesized by the reaction of p-tert-butylcalix4]arene (1a) or calixl41arene (1b) with glycol bis(2-chloroacetate) (2). The conditions to improve the yields of double calix4]arenes have been discussed.