Derivate des Benzo[1.3]dioxols, 44 [1]Darstellung von p-chinoiden Brenzkatechinmethylenethern / Derivatives of 1,3-Benzodioxoles, 44Preparation of 1,4-Benzoquinones Fused to Cyclic Diethers

Abstract

Abstract The preparation of 5,6-dimethyl- (1g), 5-methoxy-6-methyl-1,3-benzodioxole-4,7- quinone(1k), 6,7-dimethyl-1,4-benzodioxan-5,8-quinone (3e), 7,8-dimethyl-3,4-dihydro- 2H-1,5-benzodioxepin-6,9-quinone (4e), 8,9-dimethyl-2,3,4,5-tetrahydro-1,6-benzodioxo- cin-7,10-quinone (5f) and of 9,10-dimethyl-3,4,5,6-tetrahydro-2H-1,7-benzodioxonin-8,11-quinone (6e) by potassiumnitrosodisulfonate-oxidation of the phenols 1f, 1j, 3d, 4d, 5e, and 6d is described. To obtain the phenols by Baeyer-Villigeroxidation of the aldehydes 1e, 1i, 3c, 4c, 5d, 6c, the cyclic ethers are subjected to bromination, bromine-lithium-exchange, and formylation of the lithium-compounds.