Iron pentacarbonyl ligands on silver scorpionates.

Fluorinated tris(pyrazolyl)borate supporting ligands enable the stabilization of silver(I) bonded to a neutral, organometallic Fe(CO) ligand. The Ag-Fe interaction in these molecules is mainly electrostatic in nature, but σ-donor and backbonding contributions between the two metal fragments also play notable roles, which can be modulated by the scorpionate substituents.

Supported Lanthanum Borohydride Catalyzes CH Borylation Inside Zeolite Micropores.

The zeolite-supported lanthanide La(BH ) -HY catalyzes C-H borylation of benzene with pinacolborane (HBpin), providing a complementary approach to precious, late transition metal-catalyzed borylations. The reactive catalytic species are generated from La grafted at the Brønsted acid sites (BAS) in micropores of the zeolite, whereas silanoate- and aluminoate-grafted sites are inactive under the reaction conditions. During typical catalytic borylations, conversion to phenyl pinacolborane (PhBpin) is zero-order in HBpin concentration.

Indirect Access to Carbene Adducts of Bismuth- and Antimony-Substituted Phosphaketene and Their Unusual Thermal Transformation to Dipnictines and [(NHC)OCP][OCP].

The synthesis and thermal redox chemistry of the first antimony (Sb)- and bismuth (Bi)-phosphaketene adducts are described. When diphenylpnictogen chloride [PhPnCl (Pn = Sb or Bi)] is reacted with sodium 2-phosphaethynolate [Na[OCP]·(dioxane)], tetraphenyldipnictogen (PhPn-PnPh) compounds are produced, and an insoluble precipitate forms from solution. In contrast, when the -heterocyclic carbene adduct (NHC)-PnPhCl is combined with [Na[OCP]·(dioxane)], Sb- and Bi-phosphaketene complexes are isolated.

s-Block Multiple Bonds: Isolation of a Beryllium Imido Complex.

A common feature of d- and p-block elements is that they participate in multiple bonding. In contrast, the synthesis of compounds containing homo- or hetero-nuclear multiple bonds involving s-block elements is extremely rare. Herein, we report the synthesis, molecular structure, and computational analysis of a beryllium imido (Be=N) complex (2), which was prepared via oxidation of a molecular Be precursor (1) with trimethylsilyl azide Me SiN (TMS-N ).

Synthesis and characterization of N-heterocyclic carbene-MOEt complexes (M = Cu, Ag, Au). Analysis of solvated auxiliary-ligand free [(NHC)M] species.

We report the synthesis, characterization and computational analysis of coinage metal-ether complexes supported by N-heterocyclic carbenes (NHC), SIPr and Et2CAAC. The related water adducts are also included. The [(NHC)M]+(M = Cu, Ag, Au) species show the noteworthy ability to bind Et2O and H2O.

Carbodicarbene Bismaalkene Cations: Unravelling the Complexities of Carbene versus Carbone in Heavy Pnictogen Chemistry.

We report a combined experimental and theoretical study on the first examples of carbodicarbene (CDC)-stabilized bismuth complexes, which feature low-coordinate cationic bismuth centers with C=Bi multiple-bond character. Monocations [(CDC)Bi(Ph)Cl][SbF ] (8) and [(CDC)BiBr (THF) ][SbF ] (11), dications [(CDC)Bi(Ph)][SbF ] (9) and [(CDC)BiBr(THF) ][NTf ] (12), and trication [(CDC) Bi][NTf ] (13) have been synthesized via sequential halide abstractions from (CDC)Bi(Ph)Cl (7) and (CDC)BiBr (10). Notably, the dications and trication exhibit C Bi double dative bonds and thus represent unprecedented bismaalkene cations.

Synthesis and characterization of heterometallic complexes involving coinage metals and isoelectronic Fe(CO), [Mn(CO)] and [Fe(CO)CN] ligands.

The chemistry of coinage metal ions with Fe(CO), [Mn(CO)] and [Fe(CO)CN] has been explored using MesP and N-heterocyclic carbene supporting ligands. A comparison of [(SIPr)Au-Fe(CO)][SbF], [(CAAC)Au-Fe(CO)][SbF] and [(MesP)Au-Fe(CO)][SbF] shows that the ligand donor strength towards Au(i) follows the order MesP > CAAC > SIPr. These Fe(CO) complexes show significant blue shifts in [small nu, Greek, macron] bands relative to those observed for free Fe(CO) as a result of it serving as a net electron donor to Au(i).

A Stable, Crystalline Beryllium Radical Cation.

The alkaline-earth elements (Be, Mg, Ca, Sr, and Ba) strongly favor the formation of diamagnetic compounds in the +2 oxidation state. Herein we report a paramagnetic beryllium radical cation, [(CAAC)Be] () [CAAC = cyclic (alkyl)(amino)carbene], prepared by oxidation of a zero-valent beryllium complex with 2,2,6,6-tetramethylpiperidin-1-oxyl (TEMPO). Compound was characterized by EPR spectroscopy, elemental analysis, X-ray crystallography, and DFT calculations.

Organic Azide and Auxiliary-Ligand-Free Complexes of Coinage Metals Supported by N-Heterocyclic Carbenes.

Organic azide complexes of copper(I) and silver(I), [(SIPr)CuN(1-Ad)NN][SbF], [(SIPr)CuN(2-Ad)NN][SbF], [(SIPr)CuN(Cy)NN][SbF], and [(SIPr)AgN(1-Ad)NN][SbF] have been synthesized by using Ag[SbF] and the corresponding organic azides with (SIPr)CuBr and (SIPr)AgCl (SIPr = 1,3-bis(2,6-diisopropylphenyl)imidazolin-2-ylidene). The copper and silver organic azide complexes were characterized by various spectroscopic techniques and X-ray crystallography. Group trends of isoleptic Cu(I), Ag(I), and Au(I) organic azide complexes are presented on the basis of experimental data and a detailed computational study.

Cyclic(alkyl)(amino) Carbene-Promoted Ring Expansion of a Carbodicarbene Beryllacycle.

Recent synthetic efforts have uncovered several bond activation pathways mediated by beryllium. Having the highest charge density and electronegativity, the chemistry of beryllium often diverges from that of its heavier alkaline earth metal congeners. Herein, we report the synthesis of a new carbodicarbene beryllacycle ().

Stepwise Reduction at Magnesium and Beryllium: Cooperative Effects of Carbenes with Redox Non-Innocent α-Diimines.

In the past two decades, the organometallic chemistry of the alkaline earth elements has experienced a renaissance due in part to developments in ligand stabilization strategies. In order to expand the scope of redox chemistry known for magnesium and beryllium, we have synthesized a set of reduced magnesium and beryllium complexes and compared their resulting structural and electronic properties. The carbene-coordinated alkaline earth-halides, (CAAC)MgBr (), (SIPr)MgBr (), (CAAC)BeCl (), and (SIPr)BeCl () [CAAC = diethyl cyclic(alkyl)(amino) carbene; SIPr = 1,3-bis(2,6-diisopropylphenyl)-4,5-dihydroimidazole-2-ylidene] were combined with an α-diimine [2,2-bipyridine (bpy) or (2,6-diisopropylphenyl)-1,4-diazabutadiene (DAB)] and the appropriate stoichiometric amount of potassium graphite to form singly- and doubly-reduced compounds (CAAC)MgBr(DAB) (), (CAAC)MgBr(bpy) (), (CAAC)Mg(DAB) (), (CAAC)Be(bpy) (), and (SIPr)Be(bpy) ().

Metal-Free Electrochemical Reduction of Carbon Dioxide Mediated by Cyclic(Alkyl)(Amino) Carbenes.

Carbenes are known to activate carbon dioxide to form zwitterionic adducts. Their inherent metal-free redox activity remains understudied. Herein, we demonstrate that zwitterionic adducts of carbon dioxide formed with cyclic(alkyl)(amino) carbenes are not only redox active, but they can mediate the stoichiometric reductive disproportionation of carbon dioxide to carbon monoxide and carbonate.

Isolation of Cyclic(Alkyl)(Amino) Carbene-Bismuthinidene Mediated by a Beryllium(0) Complex.

The long-sought carbene-bismuthinidene, (CAAC)Bi(Ph), has been synthesized. Notably, this represents both the first example of a carbene-stabilized subvalent bismuth complex and the extension of the carbene-pnictinidene concept to a non-toxic metallic element (Bi). The bonding has been investigated by single-crystal X-ray diffraction studies and DFT calculations.

s-Block carbodicarbene chemistry: C(sp)-H activation and cyclization mediated by a beryllium center.

The first examples of carbodicarbene (CDC)-s-block complexes have been synthesized. The addition of base or reducing agent to a CDC-beryllium (chloride)(hexamethyldisilazide) adduct results in the unprecedented activation of a pendant C(sp3)-H bond and cyclization of the CDC to form a five-membered beryllium metallacycle. This also represents the first example of chemical activation of a CDC which transforms the ligand from monodentate neutral to chelating anionic.

Highly Reactive Cyclic(alkyl)(amino) Carbene- and N-Heterocyclic Carbene-Bismuth(III) Complexes: Synthesis, Structure, and Computations.

Cyclic(alkyl)(amino) carbene (CAAC)-stabilized complexes of phosphorus, one of the lightest group 15 elements, are well-established and can often be obtained in high yields. In contrast, analogous CAAC compounds of bismuth, the heaviest nonradioactive member of group 15, are unknown. Indeed, reactivity increases as you descend the group, and as a result there are only a few examples of N-heterocyclic carbene (NHC)-bismuth complexes.

The origin, type and hydrocarbon generation potential of organic matter in a marine-continental transitional facies shale succession (Qaidam Basin, China).

This organic-rich shale was analyzed to determine the type, origin, maturity and depositional environment of the organic matter and to evaluate the hydrocarbon generation potential of the shale. This study is based on geochemical (total carbon content, Rock-Eval pyrolysis and the molecular composition of hydrocarbons) and whole-rock petrographic (maceral composition) analyses. The petrographic analyses show that the shale penetrated by the Chaiye 2 well contains large amounts of vitrinite and sapropelinite and that the organic matter within these rocks is type III and highly mature.

Heterobimetallic Complexes Featuring Fe(CO) as a Ligand on Gold.

Iron(0) pentacarbonyl complexes of gold(I), [Mes PAu-Fe(CO) ][SbF ] (1) and [(IPr*)Au-Fe(CO) ][SbF ] (2) (Mes=2,4,6-trimethylphenyl; IPr*=1,3-bis(2,6-bis(diphenylmethyl)-4-methylphenyl)imidazol-2-ylidene) have been synthesized using Mes PAuCl and (IPr*)AuCl as the gold(I) precursor, AgSbF halide ion abstractor, and the Lewis base Fe(CO) . The Au-Fe bond lengths of these metal-only Lewis pair complexes are significantly shorter than the sum of the experimentally derived covalent radii of Au and Fe. The v̄(CO) bands of the molecules show a notable blueshift relative to those observed for free Fe(CO) , indicating a substantial reduction in Fe→CO backbonding upon its coordination to gold(I) with either Mes P or IPr* supporting ligands (L).

Heterobimetallic Silver-Iron Complexes Involving Fe(CO) Ligands.

Iron(0) pentacarbonyl is an organometallic compound with a long history. It undergoes carbonyl displacement chemistry with various donors (L), leading to molecules of the type Fe(CO)(L). The work reported here illustrates that Fe(CO) can also act as a ligand.

Probing the Reactivity of the Ce═O Multiple Bond in a Cerium(IV) Oxo Complex.

The reactivity of the cerium(IV) oxo complex [(L)Ce(═O)(HO)]·MeC(O)NH (1; L = [CoCp{P(O)(OEt)}], where Cp = η-CH) toward electrophiles and Brønsted acids has been investigated. The treatment of 1 with acetic anhydride afforded the diacetate complex [Ce(L)(OCMe)] (2). The reaction of 1 with B(CF) yielded [Ce(L)(MeCONH)][B(CF)(OH)] (3), in which the [B(CF)(OH)] anions are H-bonded to the O-bound acetamide ligands.

Heterobimetallic cerium(iv) oxo clusters supported by a tripodal oxygen ligand.

Heterometallic Ce(IV)/M (M = Mo(VI), Re(VII), V(V)) oxo clusters supported by the Kläui tripodal oxygen ligand [(η(5)-C5H5)Co{P(O)(OEt)2}3](-) (LOEt(-)) have been synthesized and structurally characterized, and the catalytic activity of the Ce(IV)/V(V) oxo cluster in the oxidation of thioanisoles has been studied. Treatment of [Ce(LOEt)Cl3] (1) with [Ag2MoO4] afforded the reported Ce(IV)/Mo(VI) cluster [H4(CeLOEt)6Mo9O38] (2), whereas that with [AgReO4] yielded the Ce(IV)/Re(VII) cluster [{LOEtCe(ReO4)2(H2O)(μ-ReO4)}2] (3) that contains an 8-membered Ce2Re2O4 ring. Treatment of 1 with [Ag3VO4] afforded the Ce(IV)/V(V) cluster [H2(CeLOEt)4(V[double bond, length as m-dash]O)4(μ4-O)(μ3-O)12] (4) containing a {Ce4V4O13} oxo-metallic core.

Iodosylbenzene and iodylbenzene adducts of cerium(IV) complexes bearing chelating oxygen ligands.

Reactions of [Ce(IV)(LOEt)2Cl2] (LOEt(-) = [Co(η(5)-C5H5){P(O)(OEt)2}3](-)) and [Ce(μ-O){N(Pr(i)2PO)2}4Cl2] with PhIO afford the λ3-iodane complexes [Ce(IV)(LOEt)2{OI(Cl)Ph}2] and [Ce{N(Pr(i)2PO)2}3{OI(Cl)Ph}], respectively, whereas that between [Ce(IV)(LOEt)2Cl2] and PhIO2 or excess PhIO yields the λ5-iodane adduct [Ce(IV)(LOEt)2{OI(O)ClPh}2]. The crystal structures of the Ce(IV)λ3- and λ5-iodane complexes have been determined and their oxo transfer reactivities have been investigated.

Synthesis, Structure, and Reactivity of a Tetranuclear Cerium(IV) Oxo Cluster Supported by the Kläui Tripodal Ligand [Co(η(5) -C5 H5 ){P(O)(OEt)2 }3 ](.).

A tetranuclear Ce(IV) oxo cluster compound containing the Kläui tripodal ligand [Co(η(5) -C5 H5 ){P(O)(OEt)2 }3 ](-) (LOEt (-) ) has been synthesized and its reactions with H2 O2 , CO2 , NO, and Brønsted acids have been studied. The treatment of [Ce(LOEt )(NO3 )3 ] with Et4 NOH in acetonitrile afforded the tetranuclear Ce(IV) oxo cluster [Ce4 (LOEt )4 O7 H2 ] (1) containing an adamantane-like {Ce4 (μ2 -O)6 } core with a μ4 -oxo ligand at the center. The reaction of 1 with H2 O2 resulted in the formation of the peroxo cluster [Ce4 (LOEt )4 (μ4 -O)(μ2 -O2 )4 (μ2 -OH)2 ] (2).

A tetravalent cerium complex containing a Ce=O bond.

Whereas terminal oxo complexes of transition and actinide elements are well documented, analogous lanthanide complexes have not been reported to date. Herein, we report the synthesis and structure of a cerium(IV) oxo complex, [CeO(LOEt )2 (H2 O)]⋅MeC(O)NH2 (1; LOEt (-) =[Co(η(5) -C5 H5 ){P(O)(OEt)2 }3 ](-) ), featuring a short CeO bond (1.857(3) Å).

Heterometallic cerium(IV) perrhenate, permanganate, and molybdate complexes supported by the imidodiphosphinate ligand [N(i-Pr2PO)2]-.

Heterometallic cerium(IV) perrhenate, permanganate, and molybdate complexes containing the imidodiphosphinate ligand [N(i-Pr2PO)2](-) have been synthesized, and their reactivity was investigated. Treatment of Ce[N(i-Pr2PO)2]3Cl (1) with AgMO4 (M = Re, Mn) afforded Ce[N(i-Pr2PO)2]3(ReO4) (2) or Ce2[N(i-Pr2PO)2]6(MnO4)2 (3). In the solid state, 3 is composed of a [Ce2{N(i-Pr2PO)2}6(MnO4)](+) moiety featuring a weak Ce-OMn interaction [Ce-OMn distance = 2.