H. Gibson, D. Nagvekar
Oct 1, 1997
Citations
1
Influential Citations
52
Citations
Journal
Canadian Journal of Chemistry
Abstract
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 of 4 and this procedure was generalized to afford other difunctional monomers. Condensation of substituted resorcinols with 3 and subsequent transformations yielded substituted (R) 3,5-bis(11-chloro-3,6,9-trioxaundecyl-oxy)benzenes (7, 9–14). Reaction of dihalides 7 (R = COOCH3), 13 (R = CHO), and 12 (R = CH2OSi(Me)2-t-Bu) with methyl 3,5-dihydroxybenzoate (1) produced bis(5-carbomethoxy-m-phenylene)-32-crown-10 (4) (43%), 5-carbomethoxy-m-phenylene-5′-formyl-m′-phenylene-32-crown-10 (15) (32%), and the lactone (16a) (18%, derived from the initially formed 5-hydroxym...