Masakazu Nambo

Triarylmethanes and related compounds are fascinating molecules because of their structural and physical properties, many potential applications in organic functional materials, and high biological activity. Recently, catalysis has provided new synthesis routes to triarylmethanes with high selectivity and diversity, including the possibility of preparing enantiomerically enriched derivatives, which is typically challenging using classical methods. This Perspective reviews recent advances in new

Abstract Triarylmethanes, which are valuable structures in materials, sensing and pharmaceuticals, have been synthesized starting from methyl phenyl sulfone as an inexpensive and readily available template. The three aryl groups were installed through two sequential palladium‐catalyzed CH arylation reactions, followed by an arylative desulfonation. This method provides a new synthetic approach to multisubstituted triarylmethanes using readily available haloarenes and aryl boronic acids, and is

Abstract Triarylmethanes, which are valuable structures in materials, sensing and pharmaceuticals, have been synthesized starting from methyl phenyl sulfone as an inexpensive and readily available template. The three aryl groups were installed through two sequential palladium‐catalyzed CH arylation reactions, followed by an arylative desulfonation. This method provides a new synthetic approach to multisubstituted triarylmethanes using readily available haloarenes and aryl boronic acids, and is

This perspective highlights advances in the preparation and understanding of metal nanoclusters stabilized by organic ligands with a focus on <i>N</i>-heterocyclic carbenes (NHCs). We demonstrate the need for a clear understanding of the relationship between NHC properties and their resulting metal nanocluster structure and properties. We emphasize the importance of balancing nanocluster stability with the introduction of reactive sites for catalytic applications and the importance of a better u

Sulfones are common, readily available reagents that have recently attracted attention as versatile reagents for cross-coupling reactions. This Review summarizes advances in desulfonylative transformations of sulfones affected by molecular catalysis, including transition-metal catalysts, photocatalysts, and organocatalysts. In addition to catalyst choice, the design of the sulfonyl group is a critical factor to control reactivity. The concepts presented herein will provide new strategies to cons

A new organoboron-based arylation and alkenylation of C60 catalyzed by a rhodium complex was developed. A treatment of C60 with an organoboron compound in the presence of a catalytic amount of [Rh(cod)(CH3CN)2]BF4 in H2O/1,2-Cl2C6H4 furnished a functionalized fullerene (R−C60−H) with good to excellent selectivity. Aryl, heteroaryl, and alkenyl groups can be installed by the reactions using the corresponding boronic acids, pinacol esters, and potassium trifluoroborates.

An aziridine moiety on the fullerene core can serve as an acid-triggered reacting template for the controlled synthesis of a range of functionalized fullerenes that are otherwise difficult to synthesize in an efficient and selective manner. A copper-catalyzed aziridination of C(60) for the practical synthesis of aziridinofullerene 1 and acid-catalyzed reactions of 1 with mono- and bifunctional nucleophiles as well as alkynes are described. The rapid generation of structural diversity in a single

The development of fluorinated sulfone derivatives as versatile electrophiles for Suzuki–Miyaura cross-coupling reactions is described. Introducing electron-withdrawing groups on the aryl ring of the sulfone facilitates the Pd-catalyzed activation of C–SO2 bonds. Cross-coupling reactions with fluorinated sulfone electrophiles are reported, leading to a variety of multiply arylated products in good yields. The reactivity of this unusual electrophile is benchmarked versus common electrophiles and

The selective synthesis of multiarylated acetonitriles via sequential palladium-catalyzed arylations of chloroacetonitrile is reported. The three aryl groups are installed via a Pd-catalyzed Suzuki-Miyaura cross coupling reaction followed by back-to-back C-H arylations to afford triarylacetonitriles in three steps with no over-arylation at any step. The triarylacetonitrile products can be converted into highly functionalized species including tetraarylmethanes. This new strategy provides rapid a

A Pd-catalyzed tetraallylation of C(60) that selectively occurs with an unsymmetrical addition pattern has been established. Treatment of C(60) with CH(2)=CHCH(2)Cl, CH(2)=CHCH(2)SnBu(3), and PdCl(2)[P(OPh)(3)](2) in 1,2-Cl(2)C(6)H(4) at 50 degrees C afforded the tetraallylated fullerene in 74% yield with virtually complete regioselectivity. Mechanistic investigations showed that (i) tetraallylation proceeds through consecutive nucleophilic/electrophilic allylations [likely via a bis(pi-allyl)pa

A series of chiral Au₁₃ nanoclusters were synthesized <i>via</i> the direct reduction of achiral dinuclear Au(i) halide complexes ligated by <i>ortho</i>-xylyl-linked bis-<i>N</i>-heterocyclic carbene (NHC) ligands. A broad range of functional groups are tolerated as wingtip substituents, allowing for the synthesis of a variety of functionalized chiral Au₁₃ nanoclusters. Single crystal X-ray crystallography confirmed the molecular formula to be [Au₁₃(bisNHC)<sub>

Herein we report the first chiral Au₁₀ nanoclusters stabilized by chiral bis N-heterocyclic carbene (bisNHC) ligands. ESI-MS and single-crystal X-ray crystallography confirmed the molecular formula to be [Au₁₀(bisNHC)₄Br₂](O₂CCF₃)₂. The chiral Au₁₀ nanocluster adopts a linear edge-shared tetrahedral geometry with a prolate shape. DFT calculations provide insight into the electronic structure, optical absorpti

A scandium-triflate-catalyzed arylative desulfonation of diarylmethyl phenyl sulfones with arenes and heteroarenes was established. A variety of both sulfone and arene substrates were reacted to afford symmetric and nonsymmetric triarylmethanes in good yields. Further transformations of the resulting triarylmethanes and application to the concise synthesis of a bactericidal agent analogue were also demonstrated.

α-Fluoromethylarenes are common substructures in pharmaceuticals and agrochemicals, with the introduction of fluorine often resulting in improved biological activity and stability. Despite recent progress, synthetic routes to α-fluorinated diarylmethanes are still rare. Herein we describe the Pd-catalyzed Suzuki-Miyaura cross-coupling of α-fluorinated benzylic triflones with arylboronic acids affording structurally diverse α-fluorinated diarylmethanes. The ease of synthesis of fluorinated triflo

Herein, we describe the synthesis of a toroidal Au₁₀ cluster stabilized by <i>N</i>-heterocyclic carbene and halide ligands <i>via</i> reduction of the corresponding NHC-Au-X complexes (X = Cl, Br, I). The significant effect of the halide ligands on the formation, stability, and further conversions of these clusters is presented. While solutions of the chloride derivatives of Au₁₀ show no change even upon heating, the bromide derivative readily undergoes conversion to form