Intramolecular Nickel‐Catalyzed Ring‐Opening Reactions of Oxabenzonorbornadienes with C₁‐Tethered Aryl Halides: An Improvement of Method

Abstract

An improved method of the recently reported novel transition metal‐catalyzed intramolecular ring‐opening reaction of oxabenzonorbornadienes with C1‐tethered aryl halides is described. Using a nickel catalyst, fused tetracycles containing a 1,2‐dihydronaphthalen‐1‐ol framework were generated with good to excellent yields and selectivities in most cases: a result seldom obtained using the previous palladium‐catalyzed conditions. Electron‐withdrawing, electron‐donating, and bulky substituents were generally found to be well tolerated in the reaction while extension of the tether led to decreased yields.

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A DFT Study on the Mechanism and Origin of Regioselectivity in the Rhodium/Diene‐Catalyzed Ring‐Opening Reactions of C1‐Substituted Oxabenzonorbornadienes with Arylboronic Acids

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