Modulated Multicomponent Reaction Pathway by Pore-Confinement Effect in MOFs for Highly Efficient Catalysis of Low-Concentration CO.

The conversion of flue gas CO into high-value chemicals via multicomponent reactions (MCRs) offers the advantages of atom economy, bond-formation efficiency and product complexity. However, because of the competition between reaction sequences and pathways among substrates, the efficient synthesize the desired product is a great challenge. Herein, a porous noble-metal-free framework (Cu-TCA) was synthesized, which can highly effectively catalyze the multicomponent conversion of CO by modulating reaction pathways.

Exploring Singlet Carbyne Anions and Related Low-Valent Carbon Species Utilizing a Cyclic Phosphino Substituent.

ConspectusThe advancement of synthetic methodologies is fundamentally driven by a deeper understanding of the structure-reactivity relationships of reactive key intermediates. Carbyne anions are compounds featuring a monovalent anionic carbon possessing four nonbonding valence electrons, which were historically confined to theoretical constructs or observed solely within the environment of gas-phase studies. These species possess potential for applications across diverse domains of synthetic chemistry and ancillary fields.

(Phosphino)(stannyl)carbene.

The synthesis of a (phosphino)(stannyl)carbene is documented. The combination of phosphino and stannyl substituents imparts a highly ambiphilic nature to this carbene, enabling reactions with cyanide, isocyanide, and carbon monoxide. This leads to rare stannylketenimines and a stannylketene.

Selective Hydroboration of C-C Single Bonds without Transition-Metal Catalysis.

Selective hydroboration of C-C single bonds presents a fundamental challenge in the chemical industry. Previously, only catalytic systems utilizing precious metals Ir and Rh, in conjunction with N- and P- ligands, could achieve this, ensuring bond cleavage and selectivity. In sharp contrast, we discovered an unprecedented and general transition-metal-free system for the hydroboration of C-C single bonds.

Probing the Electron Accepting Ability of Phosphaphenalenes.

Phosphaphenalenes, extended π conjugates with the incorporation of phosphorus, are attractive avenues towards molecular materials for the applications in organic electronics, but their electron accepting ability have not been investigated. Herein we present systematic studies on the reductive behavior of a representative phosphaphenalene and its oxide by chemical and electrochemical methods. The chemical reduction of the phosphaphenalene by alkali metals reveals the facile P-C bond cleavage to form phosphaphenalenide anion, which functions as a transfer block for structure modification on the phosphorus atom.

Correction: Recent advances in the chemistry of isolable carbene analogues with group 13-15 elements.

Correction for 'Recent advances in the chemistry of isolable carbene analogues with group 13-15 elements' by Mian He , , 2024, https://doi.org/10.1039/D3CS00784G.

Carbene-Stabilized Phosphagermylenylidene: A Heavier Analog of Isonitrile.

Phosphagermylenylidenes (R-P═Ge), as heavier analogs of isonitriles, whether in their free state or as complexes with a Lewis base, have not been previously identified as isolable entities. In this study, we report the synthesis of a stable monomeric phosphagermylenylidene within the coordination sphere of a Lewis base under ambient conditions. This species was synthesized by Lewis base-induced dedimerization of a cyclic phosphagermylenylidene dimer or via MeSiCl elimination from a phosphinochlorogermylene framework.

A stable rhodium-coordinated carbene with a σπ electronic configuration.

Isolable singlet carbenes have universally adopted a σπ electronic state, making them σ-donors and π-acceptors. We present a rhodium-coordinated, cationic cyclic diphosphinocarbene with a σπ ground state configuration. Nuclear magnetic resonance spectroscopy studies show a carbene carbon chemical shift below -30.

Derivatization of an Alkylideneborane with B═C Bond Cleavage.

We present the synthesis, structural characterization, and reactivity of alkylideneborane , supported by π-donating N-heterocyclic imino and σ-donating N-heterocyclic carbene (NHC) ligands. The incorporation of these ligands effectively weakens the B═C bond strength, leading to enhanced reactivity. Consequently, selective cleavage of the B═C bond can be achieved using pyridine--oxide, sulfur, and selenium, resulting in the formation of 1,3-dioxa-2,4-diboretane , thioxoborane , and selenoborane , respectively.

Utilizing bis(imino)dihydroacridanide pincer ligands in p-block chemistry: synthesis and catalysis of an antimony monocation salt.

We present the synthesis and characterization of an Sb(III) monocation salt stabilized by a bulky bis(imino)dihydroacridanide pincer ligand. The Lewis acidity of the Sb cation is quantified using the Guttmann-Beckett method and confirmed by its reaction with 4-dimethylaminopyridine, which forms a Lewis acid-base adduct. This Sb cation exhibits catalytic activity in the cyanosilylation of arylketones.

BN Analogue of Butadiyne: A Platform for Dinitrogen Release and Reduction.

Exploration of the metallomimetic chemistry of main group elements is of the utmost importance from the perspective of both fundamental research and potential applications. Here, we report the synthesis, bonding analysis, and reactivities of an isolable diiminoborane, Mes*B≡N─N≡BMes* (Mes* = 2,4,6-tri--butylphenyl) (), a BN analogue of butadiyne. This species is characterized by a conjugated B≡N─N≡B moiety, a structural feature that enables the controlled release of N when it is exposed to organic nitriles.

Utilization of a Tris(carbene)borate Ligand for Umpolung Reactivity of a Nucleophilic Tin(II) Cation Salt.

We show that a tris(carbene)borate (TCB) ligand, namely [PhB(BuIm)] ([PhB(BuIm)] = phenyltris(3--butylimidazol-2-ylidene)borato), is capable of stabilizing an unprecedented nucleophilic Sn(II) cation salt. Unlike known Sn(II) cations, the strong electron-donating ability of [PhB(BuIm)] makes the cationic tin atom electron-rich, σ-donating yet slightly π-accepting, which allows for the ensuing facile oxidation with -chloranil and S as well as coordination with coinage metals. The former oxidations give the Sn(IV) cation salts, while the latter reactions produce the metal complexes.

Synthesis and reactivity of a μ-1,2-dinitrogen dinickel(II) complex with a C-H activated silaamidinate pincer ligand.

Reaction of the silaamidinate nickel bromide LSi(NAr)NiBrLi(thf)(OEt) (L = PhC(NBu), Ar = 2,6-iPrCH, 1) with NaHBEt led to intramolecular C-H activation with the formation of the μ-1,2-dinitrogen dinickel pincer complex [LSi(NAr)(NAr)Ni](μ-1,2-N) (Ar = 2-C(CH)-6-iPrCH, 2). Single-crystal X-ray diffraction analysis of 2 disclosed a square planar Ni(II) atom bridged by N. Reaction of 2 with carbon monoxide and 2,6-dimethylphenyl isocyanide yielded square planar carbonyl and isocyanide complexes 3 and 4 with release of N.

Synthesis of Cationic Silaamidinate Germylenes and Stannylenes and the Catalytic Application for Hydroboration of Pyridines.

The N-heterocyclic germylenes and stannylenes LSi(NAr)EX (L = PhC(NBu), Ar = 2,6-PrCH; E = Ge, Sn; X = Cl, CFSO, BPh) supported by the bulky silaamidinate ligand [LSi(NAr)] have been synthesized and fully characterized. The germylene triflate LSi(NAr)GeOTf () and dimeric borate [LSi(NAr)Ge]ClBPh () enabled highly regio- and chemoselective catalytic hydroboration of pyridines and may represent the most active catalytic system for the transformation. DFT calculations disclosed that the cationic germylene [LSi(NAr)Ge] with a low-lying LUMO energy initiated the catalytic process.

Planar Polycyclic Oxaphosphoranes Incorporating a Benzophosphole Unit.

A facile method to synthesize quaternized benzophospholes on gram scale was reported, and the products were isolated by simple filtration. During this research, a series of σ-oxaphosphoranes incorporating polycyclic aromatic hydrocarbons (PAHs) were obtained. The grafting of α-phenolate groups on the phosphorus center enhances the coplanarity of the system.

A 3-dimensional spiro-functionalized platinum(II) complex to suppress intermolecular π-π and Pt···Pt supramolecular interactions for a high-performance electrophosphorescent device.

A 3-D platinum(II)-based spirometal complex has been designed and synthesized to suppress aggregation and excimer emission. A prototype phosphorescent organic light-emitting device exhibits the high-performance orange emission with an external quantum efficiency of up to 5.2%.