Abstract Single atom (SA) catalysis, over the last 10 years, has become a forefront in heterogeneous electrocatalysis, and most recently also photocatalysis. Most crucial when engineering SA catalyst/support system is creation of defined anchoring points on support surface to stabilize reactive sites. Here, so far unexplored but evidently very effective approach trap SAs broadly used photocatalyst platform introduced. In self‐organized anodic TiO 2 nanotubes, high degree stress incorporated...

The synthesis, characterization, and reactivity of a series cobalt terminal imido complexes supported by an N-anchored tripodal tris(carbene) chelate is described, including Co-supported singlet nitrene. Reaction the CoI precursor [(TIMMNmes)CoI](PF6) (TIMMNmes = tris-[2-(3-mesityl-imidazolin-2-ylidene)-methyl]amine) with p-methoxyphenyl azide yields CoIII imide [(TIMMNmes)CoIII(NAnisole)](PF6) (1). Treatment 1 equiv [FeCp2](PF6) at -35 °C affords formal CoIV complex...

Illumination of anatase in an aqueous methanolic solution leads to the formation Ti3+ sites that are catalytically active for generation dihydrogen (H2 ). With increasing illumination time, a light-induced self-amplification photocatalytic H2 production rate can be observed. The effect is characterized by electron paramagnetic resonance (EPR) spectroscopy, reflectivity, and photoelectrochemical techniques. Combined measurements rates situ EPR spectroscopic observation over time with AM 1.5G...

Abstract We report the synthesis of a unique cubic metal–organic framework (MOF), Fe‐HHTP‐MOF, comprising hexahydroxytriphenylene (HHTP) supertetrahedral units and Fe III ions, arranged in diamond topology. The MOF is synthesized under solvothermal conditions, yielding highly crystalline, deep black powder, with crystallites 300–500 nm size tetrahedral morphology. Nitrogen sorption analysis indicates porous material surface area exceeding 1400 m 2 g −1 . Furthermore, Fe‐HHTP‐MOF shows...

We introduce the arsenido ligand onto TiIV ion, yielding a remarkably covalent Ti≡As bond and parent arsinidene Ti═AsH moiety. An anionic is assembled via reductive decarbonylation involving discrete TiII salt [K(cryptand)][(PN)2TiCl] (1) (cryptand = 222-Kryptofix) Na(OCAs)(dioxane)1.5 in thf/toluene to produce mixed alkali ate-complex [(PN)2Ti(As)]2(μ2-KNa(thf)2) (2) [K(cryptand)][(PN)2Ti≡As] (3) featuring terminal ligand. Protonation of 2 or 3 with various weak acids cleanly forms...

Herein we introduce for the first time a reduced “grey” brookite TiO₂photocatalyst, produced by thermal hydrogenation of nanoparticles, that shows remarkable noble metal free photocatalytic H₂evolution.

The reaction of the cobalt(I) complex [(TIMMNmes )CoI ](BPh4 ) (2) (TIMMNmes =tris-[2-(3-mesitylimidazolin-2-ylidene)methyl]amine) with 1-adamantylazide yields cobalt(III) imido )CoIII (NAd)](BPh4 (3) concomitant release dinitrogen. N-anchor in diamagnetic 3 features an unusual, planar tertiary amine, which results from repulsive electrostatic interaction filled d(z2 )-orbital cobalt ion and negative hyperconjugation neighboring methylene groups. One-electron oxidation [FeCp2 ](OTf) provides...

Abstract Reaction of the Co I complex [(TIMMN mes )Co ](PF 6 ) ( 1 (TIMMN = t ris ‐[2‐(3‐mesityl‐ im idazolin‐2‐ylidene)‐ m ethyl]ami n e) with mesityl azide yields III imide (NMes)](PF 2 ). Oxidation [FeCp provides access to a rare imidyl )Co(NMes)](PF 3 Single‐crystal X‐ray diffractometry and EPR spectroscopy confirm molecular structure its S ground state. ENDOR, absorption computational analyses indicate ligand‐based oxidation; thus, an imidyl‐radical electronic for . Migratory insertion...

Manganese complexes with polydentate quinol-containing ligands are found to catalyze the degradation of superoxide through inner-sphere mechanisms. The redox activity ligand stabilizes higher-valent manganese species.

The activation of chalcogen–chalcogen bonds using organometallic uranium complexes has been well documented for S–S, Se–Se, and Te–Te bonds. In stark contrast, reports concerning the ability a complex to activate O–O bond an organic peroxide are exceedingly rare. Herein, we describe cleavage 9,10-diphenylanthracene-9,10-endoperoxide in nonaqueous media, mediated by uranium(III) precursor [((Me,AdArO)3N)UIII(dme)] generate stable uranium(V) bis-alkoxide complex, namely,...

We describe a new type of nitrogen-centered polycyclic scaffold comprising unique combination 5-, 6-, and 7-membered rings. The compound is accessible through an intramolecular oxidative cyclodehydrogenation tri(1-naphthyl)amine. To the best our knowledge this very first example direct 3-fold cyclization triarylamine under conditions. unusual ring fusion motif confirmed by X-ray crystallography impact on electronic photophysical properties investigated both experimentally theoretically based...

Defined substoichiometric titanium oxides (Ti$_x$O$_{2x-1}$ with $3 < x 10$) called Magneli phases have been investigated mostly for their unusual high conductivity and metal-like behavior. In photocatalysis, phase containing titania particles reported to provide favorable charge separation resulting in enhanced reaction efficiency. the current work we describe a one-step synthesis of Magneli-containing mixed nanoparticles that carry directly integrated minute amounts Pt. Phase optimized...

Examples of stable 3d transition metal methylidene complexes are extremely rare. Here we report an isolable and vanadium complex, [(PNP)V(=NAr)(=CH2)] (PNP = N[2-PiPr2-4-methylphenyl]−, Ar 2,6-iPr2C6H3), via H atom transfer (HAT) from [(PNP)V(NHAr)(CH3)] or [(PNP)V(=NAr)(CH3)] using two one equivalents the TEMPO radical (TEMPO (2,2,6,6-tetramethylpiperidin-1-yl)oxyl), respectively. Alternatively, moiety can also be formed treatment transient [(PNP)V=NAr] with Wittig reagent, H2CPPh3....

Abstract Black TiO 2 in various forms has been investigated for numerous photochemical applications. In photocatalytic water splitting, “grey” titania have reported to reach considerable H generation rates without using a noble metal co‐catalyst. Up now, variety of anatase powders or other morphologies grey and black forms. Here we describe that hydrothermal titanate/anatase nanotubes can show strong free activity. For optimized “blackening” conditions, drastically higher production be...

Using the potentially tridentate

Decarbonylation along with P-atom transfer from the phosphaethynolate anion, PCO- , to NbIV complex [(PNP)NbCl2 (Nt BuAr)] (1) (PNP=N[2-Pi Pr2 -4-methylphenyl]2- ; Ar=3,5-Me2 C6 H3 ) results in its coupling one of phosphine arms pincer ligand produce a phosphanylidene phosphorane [(PNPP)NbCl(Nt (2). Reduction 2 CoCp*2 cleaves P-P bond form first neutral and terminal phosphido group 5 transition metal, namely, [(PNP)Nb≡P(Nt (3). Theoretical studies have been used understand both reductive...

Abstract Three linear dimers with two redox‐active planarized triphenylamines were synthesized and their structures verified by X‐ray crystallography. Their radical cations, which exhibit electron self‐exchange between the redox centers, are of great interest. This process was thoroughly investigated means paramagnetic resonance spectroscopy, absorption (time‐dependent) density functional theory calculations. A comparison key parameters transfer non‐planarized nitrogen‐centered building...

Abstract Lithium trimethylsilyldiazomethanide and a cobalt (II) precursor with an N‐anchored tris ‐NHC (TIMEN mes ) ligand provide access to the nitrilimide 1 . Complex was structurally characterized by single‐crystal X‐ray diffractometry (SC‐XRD) its electronic structure examined in detail, including EPR spectroscopy, SQUID magnetometry computational analyses. The desilylation of C ‐(trimethylsilyl)nitrilimide reveals transient complex elusive diazomethanediide ligand, which substitutes one...

Abstract The nitrido‐ate complex [(PN) 2 Ti(N){μ ‐K(OEt )}] ( 1 ) (PN − =(N‐(2‐P i Pr ‐4‐methylphenyl)‐2,4,6‐Me 3 C 6 H reductively couples CO and isocyanides in the presence of DME or cryptand (Kryptofix222), to form rare, five‐coordinate Ti II complexes having a linear cumulene motif, [K(L)][(PN) Ti(NCE)] (E=O, L=Kryptofix222, ); E=NAd, L=3 DME, E=N t Bu, 4 5 )). Oxidation – with [Fc][OTf] afforded an isostructural III center containing neutral cumulene, E=NAd 7 ), N Bu 8 ))...

Transmetallation of [VCl3(THF)3] and [TlTptBu,Me] afforded [(TptBu,Me)VCl2] (1, TptBu,Me = hydro-tris(3-tert-butyl-5-methylpyrazol-1-yl)borate), which was reduced with KC8 to form a C3v symmetric VII complex, [(TptBu,Me)VCl] (2). Complex 1 has high-spin (S 1) ground state displays rhombic high-frequency -field electron paramagnetic resonance (HFEPR) spectra, while complex 2 an S 3/2 4A2 observable by conventional EPR spectroscopy. reacts NaN3 the VV nitride-azide [(TptBu,Me)V≡N(N3)] (3). A...

Oxidation of the low-spin FeIV imido complex [{(tBupyrr)2py}Fe═NAd] (1) ((tBupyrr)2py2– = 2,6-bis(3,5-di-tert-butyl-pyrrolyl)pyridine, Ad 1-adamantyl) with AgOAc or AgNO3 promotes reductive N–N bond coupling former nitrogen a pyrrole to form respective ferric hydrazido-like pincer complexes [{(tBupyrrNAd)(tBupyrr)py}Fe(κ2-X)] (X OAc–, 2OAc; NO3–, 2NO3). Reduction 2OAc KC8 cleaves reform ligand in 1, whereas acid-mediated demetalation 2NO3 yields free hydrazine [(tBupyrrNHAd)(tBupyrrH)py]...

Oxidative addition of 1.5 equiv bromine or iodine to a Ir(I) sulfoxide pincer complex affords the corresponding Ir(IV) tris-bromido tris-iodido complexes, respectively. The unprecedented trap-free reductive elimination from Ir(IV)-iodido is induced by coordination ligands donor solvents. In case added I-, isostructural tris-iodo Ir(III)-ate quickly generated, which then can be readily reoxidized with FcPF6 electrochemically. DFT calculations indicate an "inverted ligand field" in complexes...

Abstract Recently, black and grey titania in various morphologies have been intensively investigated for their high performance photocatalytic H 2 generation. Here we use nanosheets (NSs) with a large percentage of (001) facets hydrogenate them to activate suitable Ti 3+ -O v defects co-catalyst free Key highly active NS-catalyst is the prevention serious deformation sintering during thermal hydrogenation. In this work, present systematic investigation different thermally treated NSs...

Abstract In recent years, the defect engineering of titania via reduction treatments has shown a high potential for enabling efficient and co-catalyst-free photocatalytic H 2 generation from methanol/water solutions. However, simultaneously alters several properties TiO . Here, we use pristine (white) hydrogenated (gray) anatase nanosheets with dominant (001) facets. By comparing electrical conductivity, photocurrent spectra, transient response, evolution, show that increased conductivity or...

Abstract We report the synthesis of a unique cubic metal–organic framework (MOF), Fe‐HHTP‐MOF, comprising hexahydroxytriphenylene (HHTP) supertetrahedral units and Fe III ions, arranged in diamond topology. The MOF is synthesized under solvothermal conditions, yielding highly crystalline, deep black powder, with crystallites 300–500 nm size tetrahedral morphology. Nitrogen sorption analysis indicates porous material surface area exceeding 1400 m 2 g −1 . Furthermore, Fe‐HHTP‐MOF shows...