Oligo(ether‐sulfones), 2 . Synthesis of a novel macrocyclic aromatic ether sulfone bearing two carboxylic groups and the corresponding polyamide via direct condensation of the macrocycle with 4,4′‐diaminodiphenylmethane

A new macrocyclic arylene ether sulfone bearing two carboxylic groups, 4 , was prepared by use of pseudo high dilution techniques. In a first step, 4,4‐bis[4‐(4‐(4‐chlorophenylsulfonyl)phenoxy)phenyl]pentanoic acid ( 3 ) was prepared from bis(4‐chlorophenyl)sulfone ( 1 ) and an excess of 4,4‐bis(4‐hydroxyphenyl)pentanoic acid ( 2 ). Then, the purified trimer 3 was cyclocondensed with 4,4‐bis(4‐hydroxyphenyl)pentanoic acid ( 2 ), yielding the bifunctionalized macrocycle 4 . The existence of the ring‐shaped molecule was proved by use of MALDI‐TOF, NMR‐ and IR‐spectroscopy. The free carboxylic groups of 4 were used to build up polyamides that contain the macrocycle in the main chain and 4,4′‐diaminodiphenylmethane ( 5 ) as an aromatic diamine.