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A copper-catalyzed asymmetric allylic substitution of γ,γ-disubstituted allyl phosphates with arylboronates has been developed for the construction of quaternary stereocenters. High regio- and enantioselectivities have been achieved by employing a hydroxy-bearing chiral N-heterocyclic carbene ligand, and both E and Z substrates provide the same enantiomer as the major product. The mechanistic aspect of this catalysis has also been investigated to find that a 1:1 copper/ligand complex is most likely responsible for the present asymmetric catalysis, and the reaction proceeds with almost perfect 1,3-anti stereochemistry with respect to the allylic electrophile.

Title reaction provides access to γ-substitution products (III), (VI) and (VIII) with high regio- and enantioselectivity.

The 1,4-addition of organoboronates (II) and (VII) towards alkylidene cyanoacetates (I) and (VI) is smoothly catalyzed by a chiral Cu(I)—NHC complex to give, after decarboxylation, enantioenriched nitriles (IV) and (IX), resp., in high yields and enantioselectivities ( up to 94% e.e.).

A highly diastereoselective methodology for the preparation of various substituted piperidines via Negishi cross-couplings with (hetero)aryl iodides was developed. Depending on the position of the C−Zn bond relative to the nitrogen (position 2 vs position 4), the stereoselectivity of the coupling can be directed toward either the trans- or cis-2,4-disubstituted products. Density functional theory calculations on the relative stabilities of the Zn and Pd intermediates were performed to explain the high diastereoselectivities obtained. A novel 1,2-migration of Pd further expands this method to the stereoselective preparation of 5-aryl-2,5-disubstituted piperidines.

A copper-catalyzed addition of arylboronates to isatins has been developed to give 3-aryl-3-hydroxy-2-oxindoles under mild conditions. The catalytic cycle of this process has been examined through a series of stoichiometric reactions and an effective asymmetric variant has also been described by the use of a chiral N-heterocyclic carbene ligand.

Through the structural analysis of bicyclo[3.3.1]nona-2,6-dienes, new C2-symmetric chiral diene ligands 1 based on 3,7-disubstituted bicyclo[3.3.1]nona-2,6-diene framework have been designed and synthesized. These chiral ligands readily bind to rhodium(I) and provide a different chiral environment from the existing chiral dienes. The rhodium complexes thus obtained act as effective catalysts for 1,4-addition of alkenyl- and arylboronic acids to various α,β-unsaturated ketones, including several combinations that were previously difficult to provide high enantioselectivity.

A nonenzymatic kinetic resolution of tertiary homoallyl alcohols has been developed through a rhodium-catalyzed retro-allylation reaction under simple conditions. Selectivity factors of up to 12 have been achieved by employing (R)-H8-binap as the ligand, and the reaction can be conducted on a preparative scale.

Asymmetric 1,3-rearrangement of an alkynyl group of alkynyl alkenyl carbinols giving β-alkynylketones took place in high yields with high enantioselectivity in the presence of a hydroxyrhodium/(R)-binap catalyst. The present method including a key β-alkynyl elimination step in the catalytic cycle is synthetically equivalent to the asymmetric conjugate addition of terminal alkynes to β-substituted enones.