Analogous copper nanoclusters (Cu) with two electron superatomic and mixed valence copper(II)/copper(I) and copper(I)/copper(0) characters.

The reported copper nanoclusters (Cu NCs) of either Cu or Cu or mixed valence (MV) Cu/Cu or Cu/Cu characters are found to be stabilized with a discrete set of ligand donors; hence, analogous Cu NCs with a common architecture supported by the same or nearly the same donor set that exhibit different MV states of Cu, such as Cu/Cu and Cu/Cu, are unknown. Such a series of highest nuclearity copper clusters supported by aromatic thiol-S donor ligands, namely [(L4)CuI15Cu(μ-S)](PF) (1), [(L4)CuI15Cu(μ-S)]ClO·8CH (2) and [(L4)CuI15Cu(DMF)](PF)·CHOH·2CH (3), where L = 2-((3-X-thiophen)-(2-yl-methylene)amino)-4-(trifluoromethyl)benzenethiol (X = H/Me), have been synthesized and their electronic structural properties have been examined and reported herein. The Cu NCs, 1 and 2, feature a central sulfido-S (S) bridged tetracopper SCu core inside a sphere-shaped CuS truncated octahedron.

Syntheses of Tungsten Imido Cyclohexylidene Complexes Using Perfluoro-t-Butanol or Hexafluoro-t-Butanol as Acids.

The fluorinated alcohols, (CF)COH (ROH) and (CF)MeCOH (ROH), react with W(NR)Cy (Cy=Cyclohexyl; R=2,6-diisopropylphenyl or 1-adamantyl) in CD at 55 °C to give cyclohexylidene complexes. Traditional routes to terminal alkylidene complexes (neopentylidene or neophylidene) have used either triflic acid or HCl (rarely), but relatively weak fluorinated acids are sufficient and active bisalkoxide catalysts are therefore prepared directly. An α hydrogen abstraction reaction to give a cyclohexylidene complex from a biscyclohexyl complex appears to be as facile as α hydrogen abstraction to give a neopentylidene or neophylidene ligand, but isomerization of a cyclohexene formed through β hydrogen abstraction is also a possibility.

Thermal Formation of Metathesis-Active Tungsten Alkylidene Complexes from Cyclohexene.

A 7-tungstabicyclo[4.3.0]nonane complex forms slowly upon addition of cyclohexene to the ethylene complex, W(NAr)(OSiPh)(CH), at 22 °C.

Well-Defined Phosphine-Free Manganese(II)-Complex-Catalyzed Synthesis of Quinolines, Pyrroles, and Pyridines.

Herein, we report a simple, phosphine-free, and inexpensive catalytic system based on a manganese(II) complex for synthesizing different important N-heterocycles such as quinolines, pyrroles, and pyridines from amino alcohols and ketones. Several control experiments, kinetic studies, and DFT calculations were carried out to support the plausible reaction mechanism. We also detected two potential intermediates in the catalytic cycle using ESI-MS analysis.

-Selective C3- and N-Alkylation of Indolines in Water under Air Using Alcohols.

We disclosed a -selective C-H and N-H bond functionalization of indolines using alcohols in water tandem dehydrogenation of -heterocycles and alcohols. A diverse range of N- and C3-alkylated indolines/indoles were accessed utilizing a new cooperative iridium catalyst. The practical applicability of this methodology was demonstrated by the preparative-scale synthesis and synthesis of a psychoactive drug, ,-dimethyltryptamine.

Reductive Alkylation of Azides and Nitroarenes with Alcohols: A Selective Route to Mono- and Dialkylated Amines.

Herein, we demonstrated an efficient protocol for reductive alkylation of azides/nitro compounds via a borrowing hydrogen (BH) method. By following this protocol, selective mono- and dialkylated amines were obtained under mild and solvent-free conditions. A series of control experiments and deuterium-labeling experiments were performed to understand this catalytic process.

Tandem transformations and multicomponent reactions utilizing alcohols following dehydrogenation strategy.

The construction of new C-C, C-N and C-O bonds by replacing hazardous and waste generating chemicals with alcohols as the greener and sustainable reagents is one of the emerging areas of research. In consequence, the borrowing hydrogen and acceptorless dehydrogenative coupling principles have received significant momentum to synthesize various alkylated molecules and N-heterocycles. In the tandem transformations and multi-component reactions, simple substrates are directly converted to new functionalities or complex molecular systems using a single reaction set-up.

Cooperative ruthenium complex catalyzed multicomponent synthesis of pyrimidines.

A new set of 2-(2-benzimidazolyl) pyridine ligand based air and moisture stable ruthenium complexes were synthesized and characterized. The catalytic behaviors of these complexes were evaluated towards the multicomponent synthesis of highly substituted pyrimidines directly from various amidines, primary alcohols, and secondary alcohols. Among all the metal complexes, 2-hydroxypyridine and benzimidazole fragments containing complex A showed the best reactivity in this reaction.

Utilization of MeOH as a C1 Building Block in Tandem Three-Component Coupling Reaction.

Ru(II) catalyzed tandem synthesis of α-branched methylated ketones via multicomponent reactions following the hydrogen borrowing process is described. This nonphosphine-based air and moisture stable catalyst efficiently produced various methylated ketones using methanol as a methylating agent. This system was found to be highly effective in three-component coupling between methanol, primary alcohols, and methyl ketones.

Mixed valence copper-sulfur clusters of highest nuclearity: a Cu wheel and a Cu nanoball.

Fully spin delocalized mixed valence copper-sulfur clusters, 1 and 2, supported by μ-sulfido and NS donor ligands are synthesized and characterized. Wheel shaped 1 consists of CuS units. The unprecedented nanoball 2 can be described as S@Cu(tetrahedron)@O(octahedron)@CuS(cage) consisting of both CuS and (μ-S)Cu units.

Bifunctional Ru(ii) complex catalysed carbon-carbon bond formation: an eco-friendly hydrogen borrowing strategy.

The atom economical borrowing hydrogen methodology enables the use of alcohols as alkylating agents for selective C-C bond formation. A bifunctional 2-(2-pyridyl-2-ol)-1,10-phenanthroline (phenpy-OH) based Ru(ii) complex (2) was found to be a highly efficient catalyst for the one-pot β-alkylation of secondary alcohols with primary alcohols and double alkylation of cyclopentanol with different primary alcohols. Exploiting the metal-ligand cooperativity in complex 2, several aromatic, aliphatic and heteroatom substituted alcohols were selectively cross-coupled in high yields using significantly low catalyst loading (0.

Electron transfer mechanism of catalytic superoxide dismutation via Cu(ii/i) complexes: evidence of cupric-superoxo/-hydroperoxo species.

To understand the electron transfer mechanisms (outer versus inner sphere) of catalytic superoxide dismutation via a Cu(ii/i) redox couple such as occur in the enzyme copper-zinc superoxide dismutase, the Cu(ii/i) complexes [(L1)2Cu](ClO4)2·CH3CN, (1·CH3CN) and [(L1)2Cu](ClO4), (2) supported by a bis-N2Sthioether ligand, 2-pyridyl-N-(2'-methylthiophenyl)methyleneimine (L1) have been synthesized and structurally characterised. Both 1 and 2 display the same cyclic voltammogram (CV) featuring a quasireversible response at E1/2 = +0.33 V vs.

Copper coordinated ligand thioether-S and NO2(-) oxidation: relevance to the CuM site of hydroxylases.

In order to gain insight into the coordination site and oxidative activity of the CuM site of hydroxylases such as peptidylglycine α-hydroxylating monooxygenase (PHM), dopamine β-monooxygenase (DβM), and tyramine β-monooxygenase (TβM), we have synthesized, characterized and studied the oxidation chemistry of copper complexes chelated by tridentate N2Sthioether, N2Osulfoxide or N2Osulfone donor sets. The ligands are those of N-2-methylthiophenyl-2'-pyridinecarboxamide (HL1), and the oxidized variants, N-2-methylsulfenatophenyl-2'-pyridinecarboxamide (HL1(SO)), and N-2-methylsulfinatophenyl-2'-pyridinecarboxamide (HL1(SO2)). Our studies afforded the complexes [(L1)Cu(II)(H2O)](ClO4)·H2O (1·H2O), {[(L1(SO))Cu(II)(CH3CN)](ClO4)}n (2), [(L1)Cu(II)(ONO)] (3), [(L1(SO))Cu(II)(ONO)]n (4), [(L1)Cu(II)(NO3)]n (5), [(L1(SO))Cu(II)(NO3)]n (6) and [(L1(SO2))Cu(II)(NO3)] (7).

Ligand centered radical pathway in catechol oxidase activity with a trinuclear zinc-based model: synthesis, structural characterization and luminescence properties.

A new trinuclear zinc(II) complex, [Zn3(L)(NCS)2](NO3)2·CH3OH·H2O (1), of a (N,O)-donor compartmental Schiff base ligand (H2L=N,N'-bis(3-methoxysalicylidene)-1,3-diamino-2-propanol), has been synthesized in crystalline phase. The zinc(II) complex has been characterized by elemental analysis, IR spectroscopy, UV-Vis spectroscopy, powder X-ray diffraction study (PXRD), (1)H NMR, EI mass spectrometry and thermogravimetric analysis. PXRD revealed that 1 crystallizes in P-1 space group with a=9.

Binary, Ternary, and Quarternary Complexes of Ruthenium(II) Involving the Flexidentate ONNS Donor Mono(4-(4-tolyl)thiosemicarbazone) of 2,6-Diacetylpyridine (L(2)H). First Report on Ruthenium Complexes of a Mono(thiosemicarbazone) of a Diketone: Crystal Structure of [Ru(L(2))(PPh(3))(2)]ClO(4).

A series of Ru(II) complexes of the ONNS donor ligand mono(4-(4-tolyl)thiosemicarbazone) of 2,6-diacetylpyridine (L(2)H) synthesized by using three different ruthenium-containing starting materials RuCl(3).xH(2)O, Ru(PPh(3))(3)Cl(2), and [Ru(NH(3))(5)Cl]Cl(2) are reported. Chemical and electrochemical studies of the complexes [Ru(L(2))(PPh(3))(2)]ClO(4) (1), [Ru(L(2))(PPh(3))(2)]Cl (2), [Ru(L(2))(PPh(3))]ClO(4).