A novel asymmetric ring-opening reaction of N-substituted azabenzonorbornadienes with a wide variety of substituted benzyl alcohols and the addition reaction of N-substituted azabenzonorbornadienes with thiols are reported, affording the corresponding 1,2-trans-alkoxyamino products in moderate yields with excellent enantioselectivities (up to 94% ee) and the corresponding thiol addition products in high yields with lower enantiomeric excesses (ee) in the presence of iridium catalyst, respectively. The effects of ligands, catalyst loading, solvents and additives, and temperature were also investigated. The anti-configuration of the product 3c was confirmed by X-ray crystal structure analysis. A possible mechanism for the present catalytic reaction is proposed.

A new platinum(II)-catalyzed asymmetric ring-opening addition of arylboronic acids to oxabenzonorbornadienes was developed, which afforded the corresponding cis-2-aryl-1,2-dihydronaphthalen-1-ol products in high yields (up to 97%) with moderate to good enantioselectivities (up to 89% ee) under very mild conditions. The effects of various ligands, catalyst loading, bases, solvents, and temperatures on the yield and enantioselectivity of the reaction were also investigated. The cis configuration of product 2m was confirmed by X-ray diffraction analysis. A potential mechanism for the present catalytic reaction is proposed.

A new, versatile, and highly efficient nickel-catalyzed asymmetric ring-opening (ARO) reaction of oxabenzonorbornadienes with a wide variety of arylboronic acids has been developed, yielding cis-2-aryl-1,2-dihydronaphthalen-1-ols in high yields (up to 99%) with good to excellent enantioselectivities (up to 99% ee) under very mild conditions. The effects of various nickel precursors, chiral bidentate ligands, catalyst loadings, bases, solvents, and temperatures on the yield and enantioselectivity of the reaction were also investigated. A plausible mechanism was proposed to account for the formation of the corresponding cis-ring-opened products based on the X-ray structure of product 4b.

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