Rhodium-catalyzed asymmetric addition of arylboronic acids to 2H-chromenes leading to 3-arylchromane derivatives.

Asymmetric addition of arylboronic acids to 2H-chromenes proceeded in the presence of a hydroxorhodium/chiral diene catalyst to give 3-arylchromanes in high yields with high enantioselectivity. The reaction involves 1,4-Rh shift before protonation to release the addition product and to regenerate the hydroxorhodium species.

Iridium-Catalyzed Hydroarylation of Conjugated Dienes via π-Allyliridium Intermediates.

A hydroxoiridium/cod complex efficiently catalyzed hydroarylation of conjugated dienes with arenes bearing an acidic N-H bond as a directing group, which can form an amidoiridium species as an active intermediate for C-H activation. A π-allyliridium(III) complex was isolated as a key intermediate leading to the addition product.

Hydroxoiridium-Catalyzed Hydroarylation of Alkynes and Bicycloalkenes with N-Sulfonylbenzamides.

Hydroxoiridium complexes efficiently catalyzed the hydroarylation of alkynes and bicycloalkenes with N-sulfonylbenzamides via C-H activation to give the corresponding ortho-alkenylation and alkylation products in high yields.

Asymmetric Cyclization of N-Sulfonyl Alkenyl Amides Catalyzed by Iridium/Chiral Diene Complexes.

Iridium/chiral diene complexes efficiently catalyzed the asymmetric cyclization of N-sulfonyl alkenyl amides to give the corresponding 2-pyrrolidone derivatives with high enantioselectivity. A mechanistic study revealed that the reaction proceeds via nucleophilic attack of the amide on the alkene moiety.

Iridium-catalyzed asymmetric [3+2] annulation of aromatic ketimines with alkynes via C-H activation: unexpected inversion of the enantioselectivity induced by protic acids.

A cationic iridium/binap catalyst enabled the asymmetric [3+2] annulation of cyclic N-acyl ketimines with internal alkynes via C-H activation to give spiroaminoindene derivatives with high enantioselectivity. The stereochemical course of this annulation was switchable by acid additives.

Stereoselective hydroacylation of bicyclic alkenes with 2-hydroxybenzaldehydes catalyzed by hydroxoiridium/diene complexes.

A hydroxoiridium complex coordinated with 1,5-cyclooctadiene efficiently catalyzed the hydroacylation of bicyclic alkenes with 2-hydroxybenzaldehyde and its derivatives in high yields with high stereoselectivity.

Iridium-catalyzed asymmetric cyclization of alkenoic acids leading to γ-lactones.

Asymmetric cyclization of alkenoic acids was realized by the use of an iridium/chiral bisphosphine catalyst, giving high yields of the corresponding γ-lactones with good enantioselectivity.

Catalytic [3 + 2] annulation of ketimines with alkynes via C-H activation by a cationic iridium(cod) complex.

[3 + 2] Annulation of ketimines with internal and terminal alkynes proceeded via C-H activation to give aminoindene derivatives in high yields, which is catalyzed by a cationic iridium complex coordinated with 1,5-cyclooctadiene (cod).

Palladium-catalyzed asymmetric synthesis of 2-pyrrolidinones with a quaternary carbon stereocenter.

A palladium-catalyzed asymmetric synthesis of 2-pyrrolidinones with a quaternary stereocenter at the 3-position has been achieved by the reaction of γ-methylidene-δ-valerolactones with alkyl isocyanates. High enantioselectivity has been realized by employing a newly synthesized chiral phosphoramidite ligand.