Naphthalene-1,4,5(8H)-triones (17) and (18) prepared in a three-step approach from the corresponding acylbenzoquinones (1) and (2), undergo an unusually rapid dienone-phenol rearrangement in acetic anhydride–sulphuric acid solution to give 5-acetoxy-7,8-dimethyl- and 5-acetoxy-6,7,8-trimethyl-1,4-naphthoquinone (19) and (20) in good yields.
由三步法由相应的酰基苯醌(1)和(2)制备的
萘1,4,5(8 H)-三酮(17)和(18)在
乙酸酐中经历异常快的二烯酮-
苯酚重排用-
硫酸溶液以高收率得到5-乙酰氧基-7,8-二甲基-和5-乙酰氧基-6,7,8-三甲基-
1,4-萘醌(19)和(20)。