Optimization studies of the condensation of methyl 3, 5-dihydroxybenzoate (1) with tetra (ethylene glycol) dichloride (3) resulted in improvement of the yield of the 1+ 1 cyclization product, 5-carbomethoxy-m-phenylene-16-crown-5 (5), to 67%(HPLC), but no improvement in the yield (28%, HPLC) of the desired 2+ 2 product, bis (5-carbomethoxy-m-phenylene)-32- crown-10 (4). However, after optimization, a two-step procedure provided improved yields ...