Mechanism of Ligand-Controlled Regioselectivity-Switchable Copper-Catalyzed Alkylboration of Alkenes

Diboron-controlled product selectivity switch in copper-catalyzed decarboxylative substitutions of alkynyl cyclic carbonates

DFT calculations were performed to explore the mechanisms, origins of diboron-controlled divergent product selectivity and stereoselectivity in the copper-catalyzed decarboxylative substitution of alkynyl cyclic carbonates.

A mechanistic study on Cu(i) catalyzed carboxylation of the C-F bond with CO2: a DFT study

The Cu(i) catalyzed carboxylation of the C-F bond recently reported by Yu and co-workers is an excellent method for the construction of complex fluoroacrylate compounds with high regioselectivity. In the present study, theoretical calculations were carried out to investigate the detailed mechanism of the catalytic cycle and the origin of regioselectivity. The calculation results reveal that the overall catalytic cycle proceeds via the migratory insertion of difluoroalkene on the boryl-Cu(i) species, synβ-F elimination, transmetalation, and carboxylation steps. The rate determining step is the carboxylation step, and the migration insertion is the regioselectivity determining step. The regioselectivity for 2,1-insertion is consistent with Yu's experiment, and is determined by both steric and electronic effects.

C–C and C–X coupling reactions of unactivated alkyl electrophiles using copper catalysis

Copper catalysts enable cross-coupling reactions of unactivated alkyl electrophiles to generate C–C and C–X bonds.

Copper-boryl mediated organic synthesis

Organoboron compounds are valuable synthetic intermediates that find application in a diverse variety of processes including both C-X and C-C bond-forming transformations. This has been achieved by using a variety of boron derivatives. Of these, boronate esters are probably the most versatile and, reflecting this, methods for the generation of boronate esters are of considerable current interest. Given the mild reaction conditions, good functional group tolerance, and low cost of the metal catalyst, the use of copper-boryl reagents is particularly attractive. In this review, methodologies in copper-boryl chemistry are discussed and the many different transformations possible are surveyed.

Computational design of high-performance ligand for enantioselective Markovnikov hydroboration of aliphatic terminal alkenes

Finding optimal chiral ligands for transition-metal-catalyzed asymmetric reactions using trial-and-error methods is often time-consuming and costly, even if the details of the reaction mechanism are already known. Although modern computational analyses allow the prediction of the stereoselectivity, there are only very few examples for the attempted design of chiral ligands using a computational approach for the improvement of the stereoselectivity. Herein, we report a systematic method for the design of chiral ligands for the enantioselective Markovnikov hydroboration of aliphatic terminal alkenes based on a computational and experimental evaluation sequence. We developed a three-hindered-quadrant P-chirogenic bisphosphine ligand that was designed in accordance with the design guidelines derived from this method, which allowed the Markovnikov hydroboration to proceed with high enantioselectivity (up to 99% ee).

Mechanism, selectivity, and reactivity of iridium- and rhodium-catalyzed intermolecular ketone α-alkylation with unactivated olefinsviaan enamide directing strategy

DFT calculations were performed to investigate the title reaction, focusing on detailed reaction mechanism and origins of selectivity and reactivity.

Copper(i)-catalysed stereoselective debromoborylation of aliphatic 1,1-dibromo-1-alkenes with bis(pinacolato)diboron

The first example of the selective debromoborylation of gem-dibromoalkenes.

Mechanism and origins of chemo- and regioselectivities of (NHC)NiH-catalyzed cross-hydroalkenylation of vinyl ethers with α-olefins: a computational study

Density functional theory calculations were performed to investigate the (NHC)NiH-catalyzed cross-hydroalkenylation of vinyl ethers with α-olefins.

Copper/Bisphosphine Catalysts in the Internally Borylative Aminoboration of Unactivated Terminal Alkenes with Bis(pinacolato)diboron

Cu(I)/modified dppbz catalyst systems for the regioselective aminoboration of unactivated terminal alkenes have been developed. The bisphosphine-based Cu catalysis enables the introduction of the readily transformable Bpin group at the more congested internal position and shows better regioselectivity for broader terminal alkenes involving sterically demanding allylbenzenes, which are relatively challenging substrates in the previous IPrCuBr catalysis. Additionally, the second-generation catalyst systems accommodate the exo-methylene-type disubstituted alkenes to deliver the corresponding aminoborated products in good yields with a high regioselectivity.

Enantioselective Synthesis of Chiral Oxygen-Containing Heterocycles Using Copper-Catalyzed Aryl C-O Coupling Reactions via Asymmetric Desymmetrization

An enantioselective desymmetric aryl C-O coupling reaction was demonstrated under the catalysis of CuI and a chiral cyclic diamine ligand. A series of chiral oxygen-containing heterocyclic units such as 2,3-dihydrobenzofurans, chromans, and 1,4-benzodioxanes with tertiary or quaternary stereocarbon centers were synthesized with this method. DFT calculations were also carried out for a better understanding of the model for enantiocontrol.