Intramolecular Palladium-Catalyzed Ring Opening of Oxabenzonorbornadienes with C1-Tethered Aryl Halides.

The novel intramolecular ring opening of oxabenzonorbornadienes with C1-tethered aryl halides was investigated using palladium catalysts to form fused tetracyclic frameworks. The reaction was generally found to synthesize 1,2-dihydronaphthalen-1-ol products with mild selectivity but was capable of synthesizing dehydrated naphthalene products in excellent yield and selectivity. Substituent effects on oxabenzonorbornadiene and on the iodoarene were explored along with the effects of varying tether length, where an efficient reaction was observed in nearly all cases. A total of 16 examples are reported with yields ranging from 0 to 96%.