Popis: |
Summary A quantitative method for the production of 3,3′,4,4′-tetra-O-methylellagic acid was developed. Ellagic acid was fully methylated under nitrogen and in air using dimethyl sulphate and 25% guanidinium methoxide in N-methyl-2-pyrrolidone. The synthesis of a range of polymer precursors derived from 3,3′,4,4′-tetra-O-methylellagic acid are outlined, including the previously unreported 2,3,4,2′,3′,4′-hexamethoxy-6,6′-diphenoyl-dichloride, 2,3,4,2′,3′,4′-hexamethoxy-6,6′-diisocyanato-diphenyl, 2,3,4, 2′,3′,4′-hexamethoxy-6,6′-diamino-diphenyl, 2,3,4,2′,3′,4′-hexamethoxy-6,6′-dihydroxymethyl-diphenyl and 2,3,4,2′,3′,4′-hexamethoxy-diphenyl-6,6′-dialdehyde. |