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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.

Highly regioselective and efficient borylation of a variety of porphyrins has been achieved by reaction with bis(pinacolato)diboron through C-H bond activation under iridium catalysis on the basis of the synthetic protocol developed by Miyaura, Hartwig, and Smith. A boryl group can be selectively introduced at sterically uncongested positions in the peripheral aryl groups of porphyrin substrates whose peripheral beta-positions are sterically hindered. Curiously, beta substituents adjacent to the aryl group to be borylated have unexpectedly large effects on the regioselectivity, because the iridium catalyst can discriminate between subtle steric differences. Chemoselective borylation was also achieved for several functionalized porphyrins. This borylation protocol can be applied to various monomeric and oligomeric functional porphyrins, hence offering an efficient route to elaborate multiporphyrin-based molecular constructs.

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.

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.