Getting to the bottom of groundwater: The development a reliable, portable, and simple-to-use device for detecting arsenic in groundwater is urgently needed developing nations such as Bangladesh, where contaminated at root public health crisis. Toward this end, highly sensitive platform utilizing surface-enhanced Raman spectroscopy (SERS, see picture) used quantitatively detect arsenate water down 1 ppb. Detailed facts importance specialist readers are published "Supporting Information"....

While β-diketiminate (BDI or ‘nacnac’) ligands have been widely adopted to stabilize a wide range of metal ions in multiple oxidation states and coordination numbers, several occurrences these do not behave as spectators participate reactivity.

An isostructural series of four annulated actinocene complexes, M(hdcCOT) 2 (M = Th, U, Np, Pu), are reported.

The anilinium salt, [PhNH3][B(C6F5)4], has been identified as a catalyst for the hydroamination and hydroarylation of several different types alkenes with anilines. weakly coordinating counterion this acid plays key role in transformation. reaction is facile styrenes tolerates norbornene, cyclic alkenes, cyclohexadiene. Selectivity between products can be tuned using time, temperature, substrate substitution. Details regarding scope selectivity hydroamination/hydroarylation are discussed.

This review provides a brief background on the extraction of uranium from seawater as well recent work by United States Department Energy this project. The world's oceans contain at 3 parts per billion, and despite low concentration, there has been historical interest in harvesting it, mainly Japan 1980s decade. Improvements materials, chemistry, deployment methods have all made, with ultimate goal lower cost. partially realized, dropping approximately $2000 kg U3O8 extracted 1984 to $500...

Amidoxime-functionalized polymeric adsorbents are the current state-of-the-art materials for collecting uranium (U) from seawater. However, marine tests show that vanadium (V) is preferentially extracted over U and many other cations. Herein, we report a complementary comprehensive investigation integrating ab initio simulations with thermochemical titrations XAFS spectroscopy to understand unusually strong selective binding of V by polyamidoximes. While open-chain amidoxime functionalities...

Reaction of (CpSiMe3)3U or (CpSiMe3)3Nd with (Cp*Al)4 Cp*Ga (Cp* = C5Me5) afforded the isostructural complexes (CpSiMe3)3M−ECp* (M U, E Al (1); M Ga (2); Nd, (3); (4)). In case 1 and 2 were isolated in 39 90% yields, respectively, as crystalline solids characterized by single-crystal X-ray diffraction, variable-temperature 1H NMR spectroscopy, elemental analysis, magnetic susceptibility, UV−visible−NIR spectroscopy. 3 4, observed spectroscopy but not pure materials. Comparison equilibrium...

Early metal gets the H: Under 1 atm of H2, vanadium complex (PFTB=perfluoro-tert-butoxide) catalytically semihydrogenates alkynes to Z alkenes. Synthetic and DFT studies, in combination with H2/D2 NMR experiments, indicate that H2 is activated by 1,2-addition 1. Upon insertion an alkyne into VH bond A, product alkene are generated 1,2-α-NH-elimination alkenyl ligand.

New tris-amidinate actinide (Th, U) complexes containing a rare O-bound terminal phosphaethynolate (OCP - ) ligand were synthesized and fully characterized. The cyanate (OCN thiocyanate (SCN analogs prepared for comparison feature preferential N-coordination to the metals. Th(amid)3(OCP) complex reacts with Ni(COD)2 yield heterobimetallic adduct (amid) 3 Th(μ-η 1 (O):η 2 (C,P)-OCP)Ni(COD) featuring an unprecedented reduced bent fragment bridging two

Over millennia, nature has evolved an ability to selectively recognize and sequester specific metal ions by employing a wide variety of supramolecular chelators. Iron-specific molecular carriers-siderophores-are noteworthy for their structural elegance, while exhibiting some the strongest most selective binding towards ion. Development simple uranyl (UO22+) recognition motifs possessing siderophore-like selectivity, however, presents challenge. Herein we report comprehensive theoretical,...

Two-electron reduction of the amidate-supported U(III) mono(arene) complex U(TDA)3 (2) with KC8 yields anionic bis(arene) [K[2.2.2]cryptand][U(TDA)2] (3) (TDA = N-(2,6-di-isopropylphenyl)pivalamido). EPR spectroscopy, magnetic susceptibility measurements, and calculations using DFT as well multireference CASSCF methods all provide strong evidence that electronic structure 3 is best represented a 5f4 U(II) metal center bound to monoreduced arene ligand. Reactivity studies show reacts U(I)...

We report an improved synthesis of 1,1'-diaminoferrocene, employing the reduction 1,1'-diazidoferrocene with H2−Pd/C, along extensive characterization data for both compounds. Diaminoferrocene undergoes a reversible 1e- oxidation in CH3CN at potential −602 mV vs Fc0/+, one most negative redox potentials ferrocene derivative. The chemical reversibility this process was confirmed by isolation stable, 17-electron [Fc(NH2)2]+ cation as PF6-, OTf-, and TCNE- salts. In solid state,...

La[N(SiMe3)2]3 reacted with 1,3-dicyclohexylcarbodiimide in refluxing toluene to yield the mono-guanidinate complex La[CyNC(N(SiMe3)2)NCy](N(SiMe3)2)21. Compound 1 is monomeric solution; X-ray structural analysis reveals an unassociated solid state, a four-coordinate lanthanum center. Complex reacts 2,6-di-tert-butylphenol (2 equivalents) cold pentane bis(phenoxide) La[CyNC(N(SiMe3)2)NCy](OC6H3tBu2-2,6)2. X-Ray indicates similar structure that of 1, center coordinated by single guanidinate...

The synthesis and reactivity of a wide range titanium benzamidinates is described. Addition 0.5 equiv Me2Mg to the dichloride L2TiCl2 (L = PhC(NSiMe3)2) in Et2O yields chloro−alkyl derivative L2Ti(Me)Cl good yield. addition 2 PhCH2MgCl affords thermally sensitive L2Ti(CH2Ph)2 moderate Likewise, 1 results clean formation dimethyl L2TiMe2. reacts with tert-butylamine refluxing benzene form five-coordinate imido L2TiNCMe3, for which crystallographic data presented. acetone C6D6 bridging oxo...

A heterobimetallic complex with the first unsupported bond between an actinide and a group 13 element, (CpSiMe3)3U−AlCp* (Cp* = C5Me5) (1), was synthesized by reaction of (CpSiMe3)3U 1/4(Cp*Al)4 in toluene. Density functional theory calculations indicate that U−Al exhibits some covalent character resulting from Cp*Al→U charge-transfer.

A series of divalent first row triflate complexes supported by the ligand tris(2-pyridylmethyl)amine (TPA) have been investigated as oxygen reduction catalysts for fuel cell applications. [(TPA)M2+]n+ (M = Mn, Fe, Co, Ni, and Cu) derivatives were synthesized characterized X-ray crystallography, cyclic voltammetry, NMR spectroscopy, magnetic susceptibility, IR conductance measurements. The stoichiometric electrochemical O2 reactivities examined. Rotating-ring disk electrode (RRDE) voltammetry...

The discovery of a Nb(III)-mediated catalytic hydrogenation internal alkynes to (Z)-alkenes that proceeds through an unprecedented mechanism is reported. mechanistic proposal involves initial reduction the alkyne by Nb(III) complex (BDI)Nb(NtBu)(CO)2 provide Nb(V) metallacyclopropene, itself capable σ-bond metathesis reactivity with H2. resulting alkenyl hydride species then undergoes reductive elimination (Z)-alkene product and regenerate metal in oxidation state. Support for proposed...

High-valent tantalum complexes having redox-active α-diimine ligands, (α-diimine)TaCl(n) (n = 3, 4), are prepared by the reaction of TaCl(5), and an organosilicon-based reductant, 1-methyl-3,6-bis(trimethylsilyl)-1,4-cyclohexadiene. Reductive cleavage C-Cl bond polyhaloalkanes is accomplished trichlorotantalum dianionic ligands via electron transfer from whereas oxidative decomposition tetraphenylborate observed using tetrachlorotantalum with monoanionic through to ligands. Chemically...

A series of actinide-transition metal heterobimetallics has been prepared, featuring thorium, uranium, and cobalt. Complexes incorporating the binucleating ligand N[ο-(NHCH2P(i)Pr2)C6H4]3 with either Th(IV) (4) or U(IV) (5) a carbonyl bridged [Co(CO)4](-) unit were synthesized from corresponding actinide chlorides (Th: 2; U: 3) Na[Co(CO)4]. Irradiation resulting isocarbonyls ultraviolet light resulted in formation new species containing actinide-metal bonds good yields 6; 7); this photolysis...

The reduction chemistry of cobalt complexes with HPNP (HPNP = HN(CH2CH2PiPr2)2) as a supporting ligand is described. Reaction [(HPNP)CoCl2] (1) n-BuLi generated both the deprotonated Co(II) species [(PNP)CoCl] (2) along Co(I) complex [(HPNP)CoCl] (3). Products resulting from 2 KC8 vary depending upon atmosphere under which performed. Monomeric square planar [(PNP)CoN2] (4) obtained dinitrogen, whereas dimeric [(PNP)Co]2 (5) formed argon. Over time, 5 activates C–H bond in PNP to form...

A versatile, monoanionic, chelating (bis)carbene ligand (2) was used to prepare a thorium dihalide complex (3) and direduced-bpy derivative (4). CASSCF calculations suggest the involvement of multiconfigurational open-shell singlet, with main configuration corresponding Th(III)-bpy(−1) (f1π*1) electronic structure. The reactivity 4 explored in various transformations, including reactions carbonyls organic azides; latter gave rise an unusual terminal Th-imido bpy (6).