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Carbonyl addition serves as a strategically straightforward and versatile approach for synthesizing alcohols, which are often encountered within bioactive molecules. Herein, we present a ligand‐free, nickel‐catalyzed carbonyl addition process using organoboron reagents. This method enables efficient arylation of readily available ketones or aldehydes, affording a variety of tertiary and secondary alcohols. Key highlights of this protocol include the obviation of external ligands and the tolerance to many functional groups and heterocycles, thereby enhancing its practicality and utility in synthetic organic chemistry. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Transition‐metal‐catalyzed asymmetric alkylation of aldehydes represents a straightforward strategy for the synthesis of chiral secondary alcohols. However, efficient methods using organoborons as coupling reagents are rare. Herein, we report a highly enantioselective nickel‐catalyzed alkylation reaction of aldehydes, using readily available alkylborons as nucleophiles. A wide variety of chiral secondary alcohols were prepared from commercially available aldehydes with high yields. The key to the excellent enantioselectivity and chemoselectivity was the employment of a bulky C2‐symmetric chiral NHC ligand. This protocol features excellent enantiocontrol, mild conditions, and good functional group compatibility. [ABSTRACT FROM AUTHOR]

Catalytic assembly of enantiopure aliphatic amines from abundant and readily available precursors has long been recognized as a paramount challenge in synthetic chemistry. Here, we describe a mild and general copper-catalyzed hydroamination that effectively converts unactivated internal olefins—an important yet unexploited class of abundant feedstock chemicals—into highly enantioenriched α-branched amines (≥96% enantiomeric excess) featuring two minimally differentiated aliphatic substituents. This method provides a powerful means to access a broad range of advanced, highly functionalized enantioenriched amines of interest in pharmaceutical research and other areas.

This document provides spectroscopic data and experimental procedures for the synthesis of various compounds, including triarylmethanes and 1,1-diarylalkanes. The compounds were synthesized using specific reactions and characterized using NMR and IR spectroscopy. The yields and physical properties of the compounds are also reported. The data presented in the document match the literature. The compounds mentioned include (methoxymethylene)dibenzene, 1-(methoxy(phenyl)methyl)-4-methylbenzene, 1-methoxy-4-(methoxy(phenyl)methyl)benzene, (4-(methoxy(phenyl)methyl)phenyl)(methyl)sulfane, 4-(methoxy(phenyl)methyl)-N,N-dimethylaniline, 4-(4-(methoxy(phenyl)methyl)phenyl)morpholine, 4-(methoxy(phenyl)methyl)-1,1'-biphenyl, 1-fluoro-4-(methoxy(phenyl)methyl)benzene, 1-chloro-4-(methoxy(phenyl)methyl)benzene, 1-(methoxy(phenyl)methyl)-4-(trifluoromethyl)benzene, 1-(methoxy(phenyl)methyl)-2-methylbenzene, 1-methoxy-2-(methoxy(phenyl)methyl)ben [Extracted from the article]

This article provides an overview of recent advancements in C–H functionalization using NHC-Ni/Al bimetallic catalysis. The combination of N-heterocyclic carbene (NHC) ligands with nickel and aluminum catalysts allows for the activation of C–H bonds, enabling the direct functionalization of aromatic compounds. The use of bulkier and electron-donating NHC ligands has improved reactivity, and chiral NHC ligands have enabled enantioselective C–H alkylation reactions. However, challenges remain, and further research is needed to expand the range of substrates and reactions and develop new ligands and catalysis modes for wider synthetic applications. [Extracted from the article]

The chirality, or 'handedness', of a biologically active molecule can alter its physiological properties. Thus it is routine procedure in the drug discovery and development process to prepare and fully [...]

Thermal cracking permeability enhancement (TCPE) is a method to improve the coalbed methane (CBM) extraction efficiency and yield in low-permeability CBM reservoirs, but this method can change the physical and chemical properties of coal and thus affects the characteristics of coal spontaneous combustion. In order to explore the influence mechanism of TCPE on the characteristics of coal spontaneous combustion, the evolutions of oxygen adsorption capacity and chemical groups of coal under different thermal cracking parameters were measured by experiments. The following research results were obtained: On the whole, the pore and free radical structures of coal are changed after TCPE at low temperature and for a short time. The oxygen adsorption capacity and chemical activity of coal are increased, which leads to the increase of the risk of coal spontaneous combustion. However, when the coal is subjected to long-term high-temperature TCPE, the oxygen absorption capacity, and chemical reactivity are weakened. Ultimately, the risk of coal spontaneous combustion and the intensity of oxygen composite reaction become lower compared with the original state of coal. Based on these findings, it is suggested to consider long-term high-temperature thermal cracking during TCPE in CBM reservoirs. [ABSTRACT FROM AUTHOR]

Transition metal‐catalyzed C−H insertion reaction is a straightforward strategy to realize the direct functionalization of electric‐rich (hetero)arenes. The known methods generally require metal catalysts chelating with well‐defined ligands and the use of additives; a simple and practical catalytic system is still needed. We herein report a ligand‐ and additive‐free, CuCl2‐catalyzed highly selective para‐C−H carbene insertion of aniline derivatives using α‐aryl‐α‐diazo esters. A diverse array of 1,1‐diarylacetates were obtained in high yields with excellent chemo‐ and regioselectivity. [ABSTRACT FROM AUTHOR]

We herein disclose the first Ni-catalyzed Hiyama coupling of aryl halides with vinylsilanes. This protocol uses cheap, nontoxic, and stable vinyltrimethoxysilane as the vinyl donor, proceeds under mild and ligand-free conditions, furnishing a diverse variety of styrene derivatives in high yields with excellent functional group compatibility. [ABSTRACT FROM AUTHOR]