Synthesis of a new class of difunctional tetraphenylene crown ethers

Three new substituted tetraphenylene crown ethers have been made. Bis(5-car bomethoxy-1,3-phenylene)bis(p-phenylene)-(3x + 6)-crown-x, where x = 12, 16 , and 20 (11b-11d) were synthesized via [1 + 1] cyclization of methyl 3,5-b is[omega-chloro(oligoethyleneoxy)]benzoates (13b-3d) with methyl 3,5-bis[om ega-(p-hydroxyphenoxy)(oligoethyleneoxy)]benzoates (16b-6d) using K2CO3 as base and tetrabutylammonium iodide as a phase transfer agent in dimethylfor mamide (DMF). The corresponding 30-membered (x = 8) macrocycle 11a could no t be made by this approach; only the elimination product, 3,5-bis(vinyloxy) benzoic acid (19), was isolated. 16a-16d were made via alkylation of p-benz yloxyphenol (14) with 13a-13d, respectively, followed by hydrogenolysis wit h Pd/C as catalyst. No complexation of these macrocycles with dibenzylammon ium ions was detected by NMR spectroscopy, but weak complexation of lid wit h a paraquat derivative was observed.