Tetramethyl 3,7-Dihydroxybicyclonona-2,6-diene-2,4,6,8-tetracarboxylate: A Useful Companion to Meerwein's Ester. Topological Analysis of Bicyclononane Synthesis

Article abstract of DOI:10.1021/jo00219a027

The pH dependence of the condensation of dimethyl 3-oxoglutarate and malondialdehyde to produce 2,6-bis(methoxycarbonyl)phenol and tetramethyl 3,7-dihydroxybicyclo<3.3.1.>nona-2,6-diene-2,4,6,8-tetracarboxylate has been studied in detail: the yield of the former is maximal at pH 4,5, the latter at pH 7.5.The hydrolysis-decarboxylation of the latter provides a convenient route to bicyclo<3.3.1>nonane-3,7-dione.The mechanism proposed for this reaction of malonodialdehyde is also relevant to the chemistry of glyoxal and dimethyl 3-oxoglutarate.The retrosynthetic analysis of the bicyclo<3.3.1>nonane skeleton is considered from a topological perspective.