Abstract N-containing organic compounds are of vital importance to lives. Practical synthesis valuable directly from dinitrogen (N2), not through ammonia (NH3), is a holy-grail in chemistry and chemical industry. An essential step for this transformation the functionalization activated N2 units/ligands generate N−C bonds. Pioneering works transition metal-mediated direct conversion into via bond formation at metal-dinitrogen [N2-M] complexes have generated diversified coordination modes laid...

This article provides an overview of guanidine synthesis<italic>via</italic>transition-metal-catalyzed reactions including cycloaddition, guanylation and tandem guanylation/cyclization.

An efficient process involving Pd-catalyzed selective cleavage of a C(sp(3))-Si bond and consequent intramolecular C(sp(2))-Si coupling has been developed, affording benzosilolo[2,3-b]indoles as new type silicon-bridged polyheteroarene in excellent yields. Aldehyde was found for the first time to be able promote efficiency catalytic remarkably.

The development of organometallic reagents remains one the most important frontiers in synthetic chemistry. Commonly used (such as RLi and RMgBr) are typically monometallic compounds, although they aggregate many cases. When two carbon−metal bonds same molecule close proximity, however, these moieties may exhibit novel reactivity. In this Account, we outline our work on new reactions applications organo-dilithio 1,4-dilithio-1,3-butadienes. 1,4-dilithio-1,3-butadienes can be accessed readily...

Direct conversion of dinitrogen (N2) into organic compounds, not through ammonia (NH3), is great significance both fundamentally and practically. Here we report a highly efficient scandium-mediated synthetic cycle affording hydrazine derivatives (RMeN–NMeR′) directly from N2 carbon-based electrophiles. The includes three main steps: (i) reduction halogen-bridged discandium complex under leading to (N2)3–-bridged via (N2)2– intermediate; (ii) treatment the (N2)3– with methyl triflate (MeOTf),...

A series of trinuclear and dinuclear Cr(I)–N2 complexes bearing cyclopentadienyl-phosphine ligands were synthesized characterized. Further reduction the generated anionic Cr(0)–N2 complexes, which could react with Me3SiCl to afford first chromium hydrazido complex from N2 functionalization. These found be effective catalysts for transformation into N(SiMe3)3.

Since the concept of aromaticity represents one most fundamental principles in chemistry, search for unprecedented and exciting aromatic systems, therefore, continues to drive research this area. Herein we report synthesis characterization spiro metalla-aromatics, which transition metal (Pd, Pt, or Rh) is atom, that cross-conjugates two five-membered metallacycles. These metalla-aromatics tend take square planar geometries, with dihedral angle being influenced by steric repulsion between...

ConspectusThe concept of aromaticity is one the most fundamental principles in chemistry. It generally accepted that planarity a prerequisite for aromaticity, and typically more planar geometry an aromatic compound is, stronger it is. However, not always case, particularly when transition metals are involved conjugation electron delocalization systems, i.e., metalla-aromatics. Because intrinsic nature transition-metal orbitals, besides geometries, stable molecular structures metalla-aromatic...

Isolation of key intermediate complexes in dinitrogen functionalization is crucial for elucidating the mechanistic details and further investigation. Herein, synthesis characterization (μ-η1:η1-N2)(η1-N2)-Cr(I) 3 (η1-N2)2-Cr(0) 4 supported by Cp* (Cp* = C5Me5) NHC ligands were reported. Further Cr(0)-N2 complex with silyl halides delivered intermediates alternating pathway, chromium diazenido 5 side-on η2-hydrazido 6. Protonation 6 led to quantitative formation N2H4. Moreover,...

Zirconacyclopentadienes reacted with acetylenecarboxylates in the presence of a stoichiometric amount (2 equiv) copper chloride to give benzene derivatives high yields along formation mirror on wall reaction vessel. Reactions unsymmetrical zirconacyclopentadienes prepared from two different alkynes gave three selectivities. Preparation and can be done one-pot. The structure product zirconacyclopentadiene having trimethylsilyl group methyl α- β-position, respectively, acetylenedicarboxylate...

An efficient Pd-catalyzed cleavage of C(sp(3))-N bonds in secondary amines and a consequent C(sp(2))-N coupling process was developed. Various could be used to react with alkenyl or aryl dibromides, affording pyrroles indoles high yields. Cyclopentadiene-phosphine ligands, new type P-olefin ligand, were found able promote the efficiency this remarkably. A reactive Pd complex coordinated cyclopentadiene-phosphine ligand successfully isolated structurally characterized.

The commercially readily available alkyl aluminums, such as AlMe3, AlEt3, and AlEt2Cl, can serve excellent catalyst precursors for the catalytic addition of amines to carbodiimides, yielding quantitatively their corresponding trisubstituted guanidines. Aromatic C−X (X = F, Cl, Br, I) bonds, nitro NO2, terminal alkyne units survive reaction conditions. An aluminum guanidinate species has been characterized by single-crystal X-ray structural analysis confirmed be a true species.

碱, 包括无机碱和有机碱, 在过渡金属催化的有机反应中发挥着重要作用. 本文概括地介绍和讨论相关文献中碱的作用机制. 碱的作用与许多因素有关, 包括: 碱性、溶解度、电离度、溶剂、聚集度、金属离子大小、金属离子Lewis酸性、金属离子的"软硬"度、阴离子的大小、阴离子的配位作用等. 碱可用于攫取质子、中和反应体系中的酸、活化催化剂、促进催化剂再生等, 碱中金属阳离子的作用主要集中在其对碱在有机溶剂中溶解度的影响和其与底物或溶剂间相互作用力的强弱上, 碱中阴离子的作用主要表现在离子与金属的配位方式和稳定性上; 有机碱和无机碱的主要区别体现在溶解度和空间位阻的不同上. 另外, 商品碱中极少量的过渡金属杂质也有可能对反应产生影响.

Metal-containing aromatic systems (metalla-aromatics) are unique and important both experimentally theoretically. Among metalla-aromatics, six-membered metallabenzenes metallabenzynes have attracted much attention in recent years. However, reports on their superior homologues rare. In this work, the first series of dicupra[10]annulenes were isolated from reaction dilithio reagents copper salts. Single-crystal X-ray structural analysis revealed with averaged bond lengths. 7Li NMR spectra...

Ungewöhnlicher Bruch: Eine Bandbreite von Benzosilolen wird durch die Pd-katalysierte intermolekulare Kupplung 2-Silylarylbromiden mit Alkinen, einhergehend der selektiven Spaltung C(sp3)-Si-Bindungen als Schlüsselschritt erhalten (siehe Schema). Zu den Produkten gehören Benzosilole, Benzothiophen-verknüpfte Silole, leiterartige π-konjugierte Benzosilole und thiophenverbrückte 2,5-Dibenzosilole.

Abstract The selective construction of P−C bonds directly from P 4 and nucleophiles is an ideal step‐economical approach to utilizing elemental for the straightforward synthesis organophosphorus compounds. In this work, a highly efficient one‐pot reaction between 1,4‐dilithio‐1,3‐butadienes was realized, which quantitatively affords phospholyl lithium derivatives. DFT calculations indicate that mechanism significantly different well‐known stepwise cleavage P−P bond in activation. Instead,...

Abstract Organolithium compounds can behave as reductants but never oxidants in redox reactions. Reported herein is that 1,4‐dilithio‐1,3‐butadienes reacted with [Ni(cod) 2 ] (cod=1,5‐cyclooctadiene) to deliver dilithionickeloles. Single‐crystal X‐ray structural analysis revealed a coplanar structure of dilithionickeloles an averaging bond lengths. XPS data confirmed the oxidation state Ni was 2+ . 7 Li NMR spectra and theoretical calculations considerable aromatic character. In this...

Electrophilic functionalization of N2 moieties in metal dinitrogen complexes typically initiates the catalytic synthesis N-containing molecules directly from N2. Despite intensive research last six decades, how to efficiently and even quantitatively convert into diazenido hydrazido species still poses a great challenge. In this regard, systematic comprehensive investigations elucidate reaction intricacies are profound significance. Herein, we report kinetic dissection on first second...

Due to the highly chemically inert nature, direct activation and transformation of dinitrogen are challenging. Here, we disclose synthesis, isolation, derivatization (N