Cleavage of the relatively inert dinitrogen (N(2)) molecule, with its extremely strong N identical withN triple bond, has represented a major challenge to development N(2) chemistry. This report describes reductive cleavage two nitrido (N(3-)) ligands in reaction Mo(NRAr)(3), where R is C(CD(3))(2)CH(3) and Ar 3,5-C(6)H(3)(CH(3))(2'), synthetic three-coordinate molybdenum(III) complex known structure. The formation an intermediate was observed spectroscopically, conversion (with bond...

The synthesis and characterization of the complexes Mo[N(R)Ar]3 (R = C(CD3)2CH3, Ar 3,5-C6H3Me2), (μ-N2){Mo[N(R)Ar]3}2, (μ-15N2){Mo[N(R)Ar]3}2, NMo[N(R)Ar]3, 15NMo[N(R)Ar]3, Mo[N(t-Bu)Ph]3, (μ-N2){Mo[N(t-Bu)Ph]3}2, NMo[N(t-Bu)Ph]3 are described. Temperature-dependent magnetic susceptibility data indicate a quartet ground state for Mo[N(R)Ar]3. Single-crystal X-ray diffraction studies Extended absorption fine structure (EXAFS) structural Mo[N(R)Ar]3, NMo[N(R)Ar]3 reported. kinetic given...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTMethane and benzene activation via transient (tert-Bu3SiNH)2Zr:NSi-tert-Bu3Christopher C. Cummins, Steven M. Baxter, Peter T. WolczanskiCite this: J. Am. Chem. Soc. 1988, 110, 26, 8731–8733Publication Date (Print):December 1, 1988Publication History Published online1 May 2002Published inissue 1 December 1988https://pubs.acs.org/doi/10.1021/ja00234a044https://doi.org/10.1021/ja00234a044research-articleACS PublicationsRequest reuse permissionsArticle...

ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTArene-Bridged Diuranium Complexes: Inverted Sandwiches Supported by δ BackbondingPaula L. Diaconescu, Polly Arnold, Thomas A. Baker, Daniel J. Mindiola, and Christopher C. CumminsView Author Information Department of Chemistry Room 2-227 Massachusetts Institute Technology Cambridge, 02139-4307 Cite this: Am. Chem. Soc. 2000, 122, 25, 6108–6109Publication Date (Web):June 9, 2000Publication History Received23 December 1999Published online9 June...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCleavage of the Nitrous Oxide NN Bond by a Tris(amido)molybdenum(III) ComplexCatalina E. Laplaza, Aaron L. Odom, William M. Davis, Christopher C. Cummins, and John D. ProtasiewiczCite this: J. Am. Chem. Soc. 1995, 117, 17, 4999–5000Publication Date (Print):May 1, 1995Publication History Published online1 May 2002Published inissue 1 1995https://pubs.acs.org/doi/10.1021/ja00122a033https://doi.org/10.1021/ja00122a033research-articleACS...

Hydrocarbyl complexes, (tBu3SiNH)3ZrR (1-R), were prepared via metatheses of (tBu3SiNH)3ZrCl (1-Cl) with RMgX or RLi (R = Me, Et, Cy, CH2Ph, allyl, CHCH2, Ph, CH2tBu, C⋮CPh, C⋮CtBu), through addition isobutylene, H2CCCMe2, and acetylene to 1-H iBu, dma, CHCH2), by CH-bond activation; thermal 1,2-RH-elimination from 1-R produced putative (tBu3SiNH)2ZrNSitBu3 (2), which was subsequently trapped R'H. Thermolysis (∼100 °C, R Me Cy) in the presence H2, c-C3H6, CH4 cyclohexane neat C6H6,...

We report a mild method for generating the diphosphorus molecule or its synthetic equivalent in homogeneous solution; P2 allotrope of element phosphorus is normally obtained only under extreme conditions (for example, from P4 at 1100 kelvin). Diphosphorus extruded niobium complex designed this purpose and can be trapped efficiently by two equivalents an organic diene to produce organodiphosphorus compound. stabilized coordination tungsten pentacarbonyl generated similarly 25 degrees C, form...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTTri-tert-butylsilyl)imido complexes of titanium: benzene carbon-hydrogen activation and structure [(tert-Bu3SiNH)Ti]2(.mu.-NSi-tert-Bu3)2Christopher C. Cummins, Christopher P. Schaller, Gregory D. Van Duyne, Peter T. Wolczanski, A. W. Edith Chan, Roald HoffmannCite this: J. Am. Chem. Soc. 1991, 113, 8, 2985–2994Publication Date (Print):April 1, 1991Publication History Published online1 May 2002Published inissue 1 April...

The key intermediate in dinitrogen cleavage by Mo(N[t-Bu]Ar)3, 1 (Ar = 3,5-C6H3Me2), has been characterized a pair of single crystal X-ray structures. For the first time, structure (mu-N2)[Mo(N[t-Bu]Ar)3]2, 2, and product homolytic fragmentation NN bond, NMo(N[t-Bu]Ar)3, are reported. structural features 2 compared with previously reported EXAFS data. Moreover, contrasts drawn between theoretical predictions concerning magnetic properties those herein. In particular, it is shown that exists...

Silicon clears a wet path to phosphines Phosphoric acid is produced on massive scale for fertilizer by treating phosphate rock with sulfuric acid. In contrast, preparation of more elaborate phosphorus compounds used in chemical catalysis, pharmaceutical, and battery applications requires laborious generation chlorination elemental phosphorus. Geeson Cummins now show that phosphoric may also be practical source such (see the Perspective Protasiewicz). They isolated characterized phosphide...

White phosphorus, yellow arsenic, and AsP3 have been successfully activated by a complex with CrCr quintuple bond in one step leading to the formation of rare terminally bound cyclo-P42−, cyclo-As42−, cyclo-AsP3 units. The subsequent reaction an excess [W(CO)5(thf)] leads coordination {W(CO)5} fragment thermodynamically most stable form according DFT calculations. Detailed facts importance specialist readers are published as "Supporting Information". Such documents peer-reviewed, but not...

The electronic structure of the arene-bridged complex (μ-toluene)U2(N[tBu]Ar)4 (1a2-μ-toluene, Ar = 3,5-C6H3Me2) has been studied in relation to a variety mononuclear uranium amide complexes, and their properties have discussed comparatively. syntheses, molecular structures (X-ray crystal solution behavior based on variable-temperature NMR spectroscopic data), corresponding absorption near-edge UV–vis–near-IR absorption) magnetic are presented interpreted with reference results density...

An aromatic phosphorus and nitrogen ring In chemistry, the term “aromatic” denotes energy stabilization associated with electrons being shared among atoms in a ring. Benzene is best-known compound, although numerous related hydrocarbons also manifest property. Velian Cummins now report rare instance of an inorganic compound: negatively charged pentagonal composed three two atoms. Science , this issue p. 1001

The reduction of CO2 to formate using sodium borohydride was originally investigated in the 1950s. Despite this clue from chemical literature, many recent publications describe catalytic hydroboration methods leading or methoxide with more expensive and less reactive boranes such as pinacolborane. Herein we uptake 3 equiv by NaBH4, along full spectroscopic crystallographic characterization resulting triformatoborohydride, Na[HB(OCHO)3]. Conducting synthesis acetonitrile under 300 psi...

Dibenzo-7-phosphanorbornadiene compounds, RPA (A = C14H10 or anthracene), are investigated as phosphinidene sources upon thermally induced (70-90 °C) anthracene elimination. Analysis of substituent effects reveals that π-donating dialkylamide groups paramount to successful transfer; poorer π-donors give reduced no transfer. Substituent steric bulk is also implicated in Molecular beam mass spectrometry (MBMS) studies each derivative reveal derivatives be promising precursors for further...

ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTHeterodinuclear Uranium/Molybdenum Dinitrogen ComplexesAaron L. Odom, Polly Arnold, and Christopher C. CumminsView Author Information Department of Chemistry Room 2-227 Massachusetts Institute Technology Cambridge, 02139-4307 Cite this: J. Am. Chem. Soc. 1998, 120, 23, 5836–5837Publication Date (Web):May 29, 1998Publication History Received9 January 1998Published online29 May inissue 1 June...

A smooth reaction with aldehydes yielding phosphaalkenes and the oxotantalum complex [(N3N)TaO] is reported for phosphinidine complexes mentioned in title, which have a nucleophilic phosphorus atom. The crystal structure of [(N3N)-TaPR] (1, R  cyclohexyl) shows that reactive TaPR unit stabilized by its location within pocket afforded SiMe, substituents (N3N) ligand.

Three-coordinate molybdenum(III) complexes comprise a new class of reactive-yet-isolable substances. Related to well known metal–metal triple bonded dimers, the monomeric supported by sterically-demanding N-tert-alkylanilide ligands offer previously unavailable synthetic routes molybdenum–element multiple bonds. Terminal nitride, phosphide and carbide functionalities have been prepared from reactions with dinitrogen, white phosphorus carbon monoxide, respectively.

The transformation of acid chlorides (RC(O)Cl) to organic nitriles (RC[triple bond]N) by the terminal niobium nitride anion [N[triple bond]Nb(N[Np]Ar)3]- ([1a-N]-, where Np = neopentyl and Ar 3,5-Me2C6H3) via isovalent N for O(Cl) metathetical exchange is presented. Nitrido [1a-N]- obtained in a heterodinuclear N2 scission reaction employing molybdenum trisamide system, Mo(N[R]Ar)3 (R t-Bu, 2a; R Np, 2b), as partner. Reductive bridging complexes, (Ar[R]N)3Mo-(mu-N2)Nb(N[Np]Ar)3 3b; 3c) with...

The carbide anion [CMo{N(R)Ar}3]– [R = C(CD3)2CH3, Ar C6H3Me2-3,5], is obtained by deprotonation of the corresponding methylidyne compound, [HCMo{N(R)Ar}3], and characterized X-ray diffraction as its {K(benzo-15-crown-5)2}+ salt, thereby providing precedent for carbon atom a terminal substituent in transition-metal chemistry.

In the presence of NaH, reaction between N2 and Mo(N[t-Bu]Ar)3 (Ar = 3,5-C6H3Me2) proceeds at room temperature to afford NMo(N[t-Bu]Ar)3 (95%). Lewis acidic silyl triflates (Me3SiOTf + pyridine or (i-Pr)3SiOTf) mediate a acid chlorides yield acyl imidos [RC(O)NMo(N[t-Bu]Ar)3][OTf] (R Me, 92%; Ph, 75%; t-Bu, 64%). The reduction by magnesium anthracene followed treatment with Me3SiOTf affords molybdenum ketimides, R(Me3SiO)CNMo(N[t-Bu]Ar)3 82%; 77%; 46%). Exposing SnCl2 ZnCl2 produces...