Short Syntheses of Furan and Catechol Derivatives. A Synthesis of Hydrourushiol

Article abstract of DOI:10.1021/ja00345a059

The copper-catalyzed decomposition of ethyl diazopyruvate in enol ethers is shown to yield alkoxydihydrofuroates, whose exposure to acid leads to ethyl α-furoates.The latter are also the products of the copper-induced interaction of ethyl diazopyruvate with acetylenes.The conversion of one furoate into a furan and another into a furanoid terpene system is described.The Fetizon oxidation of primary β-alkoxycyclopropylcarbinols is shown to give alkoxydihydrofurans.The formation of a masked, 1,2,5-triketo system by the copper-assisted decomposition of 1-diazo-3,3-dimethoxy-2-butanone in n-butyl vinyl ether and subsequent acid-catalyzed unraveling of the resultant β-alkoxycyclopropyl ketone are portrayed.Ring scission of the intermediate in methanolic acid at elevated temperature yields veratrole.Utilization of this method of synthesis of aromatic compounds of the catehol type in the synthesis of hydrourushiol is illustrated.