“…34b, 624-632 (1979); eingegangen am 13. November 1978 5,6,7,3,4,4,5, The preparation of 5,6-dimethyl-(lg), 5-methoxy-6-methyl-l,3-benzodioxole-4,7-quinone(lk), 6,7-dimethyl-l,4-benzodioxan-5,8-quinone (3e), 7,8-dimethyl-3,4-dihydro-2H-l,5-benzodioxepin-6,9-quinone (4e), 8,9-dimethyl-2,3,4,5-tetrahydro-l,6-benzodioxocin-7,10-quinone (5f) and of 9,10-dimethyl-3,4,5,6-tetrahydro-2H-l,7-benzodioxonin-8.11-quinone (6e) by potassiumnitrosodisulfonate-oxidation of the phenols lf, lj, 3d, 4d, 5e, and 6d is described. To obtain the phenols by Baeyer-Villigeroxidation of the aldehydes le, li, 3c, 4c, 5d, 6c, the cyclic ethers are subjected to bromination, brominelithium-exchange, and formylation of the lithium-compounds.…”