Summary: | 碩士 === 國立中正大學 === 化學研究所 === 90 === 2,3-Dicyanohydroquinone (64) was oxidized with lead(IV) acetate to give 2,3-dicyano-p-benzoquinone (62). Diels-Alder cycloaddition of 62 with cyclopentadiene in refluxing benzene produced thermodynamically controlled product 1α,4α,4aα,8aα-tetrahydro-5,8-dioxo-1,4-methanonaphthalene-6,7-dicarbonitrile (61). Subsequent enolization, methoxylation, hydrolysis, esterification, reduction and bromination, transformed 61 to 6,7-dibromomethyl-5,8-dimethoxy-1,4-dihydro-1,4-methanonaphthalene (58).
Dibromide 58 was treated with two equivalents of 2-(tetra- hydropyran-2-yloxy)-1-ol (82) and 8-(tetrahydropyran-2-yloxy)-3,6-dioxaoctan-1-ol (83) by Williamson ether synthesis to give bis(tetrahydropyranyl)-protected ether 80 and 84, respectively. Deprotection of 80 and 84 under acidic condition gave corresponding diol 81 and 85, which were coupled with dibromide 58 by Williamson ether synthesis to provide (2+2) crown ether 3,12,19,28-tetramethoxy-6,9,22,25-tetraoxaheptacyclo [28.2.1.114,17. 02,29.04,27.011,20.013,18]tetratriaconta-2,4(27),11,13(18),15,19,28,31-octene (53) and 3,18,25,40-tetramethoxy-6,9,12,15,28,31,34,37-octaoxa- heptacyclo[40.2.1.120,23.02,41.04,39.017,26.019,24]hexatetracontane-2,4(39),17,19(24),21,25,40,43-octene (54).
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