By the reaction of 3-aryl-1H-benzo[f]chromenes with N-bromosuccinimide in aqueous acetone, a series of 2-aroyl-1,2-dihydronaphtho-[2,1-b]furans unsubstituted at the C-1 position were obtained as a result of formal addition of hypobromous acid to the pyran fragment and intramolecular nucleophilic substitution. This reaction is a rare example of the ring constriction in 1H-benzo[f]chromene series.

中文翻译：

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3-芳基-1H-苯并[f]色烯氧化重排为2-芳酰基-1,2-二氢萘[2,1-b]呋喃

通过 3-芳基-1 H-苯并[ f ]色烯与N-溴代琥珀酰亚胺在丙酮水溶液中的反应，一系列 2-芳酰基-1,2-二氢萘基-[2,1- b ]呋喃在 C-作为次溴酸正式加成到吡喃片段和分子内亲核取代的结果，获得了第 1 个位置。该反应是 1 H-苯并[ f ] 色烯系列中缩环的罕见例子。