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Reactivity of (triphosphine)MoIV‐nitrido complex generated by N2 splitting, toward boranes is reported. The simple adduct Mo≡N→BH3 is observed with BH3.SMe2 while 1,2 addition is evidenced with 9‐BBN leading to H−Mo=NBR2. A second addition of BH3.SMe2 is facile and forms an unprecedented complex featuring two bridging H between two B and the Mo centers. Addition of PMe3 or BH3.SMe2 promotes reductive elimination and N−H bond formation. The full sequence of functionalization at Mo≡N obtained after N2 splitting is therefore evidenced in this work. [ABSTRACT FROM AUTHOR]

Numerous synthetic models of the FeMo‐co cluster of nitrogenases have been proposed to find the simplest structure with relevant reactivity. Indeed, such structures are able to perform multi‐electrons reduction processes, such as the conversion of N2 to ammonia, and of CO2 into methane and alkenes. The most challenging parameter to imitate is indeed the central carbide ligand, which is believed to maintain the integrity of iron sulfide assembly during the course of catalytic cycles. The study proposes the use of bis(diphenylthiophosphinoyl)methanediide (SCS)2− as an ideal platform for the synthesis of bi‐ and tetra‐metallic iron complexes, in which the iron‐carbon interaction is maintained upon structural diversification and redox state changes. [ABSTRACT FROM AUTHOR]

A DFT study of several L→Al(ORF)3 (L=Lewis bases) adducts allowed the identification of (iPr2S)→Al(ORF)3 1-SiPr2 as a "stable yet reactive" adduct. 1-SiPr2 was shown to act as a masked Lewis superacid able to release Al(ORF)3 under mild conditions. It could be used to abstract a ORF- ligand from bipyMe2)Ni(ORF)2 (bipyMe2 : 6,6'-dimethyl-2,2'-dipyridyl) and generate the nickel alkoxide complex [(bipyMe2)Ni-(ORF)(iPr2S)]+[(RFO)3Al--F--Al(ORF)3]- 5. Ligand exchange of iPr2S by Ph3P yielded [(bipyMe2)Ni(ORF)(PPh3)]+[(RFO)3Al--F--Al-(ORF)3]-6. [ABSTRACT FROM AUTHOR]

Two different dinitrogen‐derived molybdenum nitrido complexes varying by their geometry, ligand spheres and oxidations states were shown to engage their N ligand in dative bonding with the strong Lewis acid B(C6F5)3. The stable adducts were assessed for frustrated Lewis pair‐type heterolytic E−H bond splitting of hydrosilanes (E=Si) and HB(C6F5)2. Whereas Si−H bond activation was achieved, HB(C6F5)2 was shown to substitute B(C6F5)3 in a quantitative or equilibrated fashion, depending on the nature of the nitrido complex. No B−H bond splitting was observed. Thermodynamics of these reactions, computed by DFT, are in agreement with the experimental outcomes. [ABSTRACT FROM AUTHOR]

Ammonia, NH3, is an essential molecule, being part of fertilizers. It is currently synthesized via the Haber–Bosch process, from the very stable dinitrogen molecule, N2 and dihydrogen, H2. This process requires high temperatures and pressures, thereby generating ca 1.6 % of the global CO2 emissions. Alternative strategies are needed to realize the functionalization of N2 to NH3 under mild conditions. Here, we show that boron‐centered radicals provide a means of activating N2 at room temperature and atmospheric pressure whilst allowing a radical process to occur, leading to the production of borylamines. Subsequent hydrolysis released NH4+, the acidic form of NH3. EPR spectroscopy supported the intermediacy of radicals in the process, corroborated by DFT calculations, which rationalized the mechanism of the N2 functionalization by R2B radicals. [ABSTRACT FROM AUTHOR]

Catalytic formation of borylamines from atmospheric N2 is achieved for the first time using a series of homogenous (triphosphine)Mo complexes. Stepwise functionalization of the (triphosphine)Mo‐nitrido complex with chloroborane led to the synthesis of the imido complex. Electrochemical characterization of the (PPP)Mo‐nitrido and (PPP)Mo‐borylimido complexes showed that the latter is much more easily reduced. [ABSTRACT FROM AUTHOR]

Reduction of high spin paramagnetic complex [(κ2-P, P′-PCH2PCy)FeCl2] 2 by two electrons under N2 resulted in the formation of two isomeric low spin diamagnetic complexes 3trans and 3cis [Fe(κ3-P,C,P′-PCPCy)(H)2(N2)]. Cristallization allowed isolation of complex 3d [Fe(κ3-P,C,P′-PCPCy)(H)2]2(μ-N2), characterized by X-ray diffraction, Mössbauer and Raman spectroscopies. DFT calculations rationalized the facile double α,α CH bond insertion into a single sp3 CH2 moiety, as well as the fast exchange positions of the hydrides in the cis dihydride complex observed by NMR spectrocscopy. [ABSTRACT FROM AUTHOR]

The direct synthesis of nitrile from N2 under mild conditions is of great importance and has attracted much interest. Herein, we report a direct conversion of N2 into nitrile via a nitrile–alkyne cross‐metathesis (NACM) process involving a N2‐derived Mo nitride. Treatment of the Mo nitride with alkyne in the presence of KOTf afforded an alkyne‐coordinated nitride, which was then transformed into MoV carbyne and the corresponding nitrile upon 1 e− oxidation. Both aryl‐ and alkyl‐substituted alkynes underwent this process smoothly. Experiments and DFT calculations have proved that the oxidation state of the Mo center plays a crucial role. This method does not rely on the nucleophilicity of the N2‐derived metal nitride, offering a novel strategy for N2 fixation chemistry. [ABSTRACT FROM AUTHOR]

Functionalization of nitrido complex [(PPhP2Cy)Mo(N)(I)] by a bis‐silane in concentrated medium generates the hydrido‐imido complex [(PPhP2Cy)Mo(H)(=NSiMe2CH2CH2SiMe2H)(I)]. Abstraction of the iodide by thallium salt TlX (X = PF6, OTf) results in a second N–Si bond formation and forms the bis‐hydride amide complex [(PPhP2Cy)Mo(H)2(NSiMe2CH2CH2SiMe2)]+. An alternative synthesis relies on the abstraction of the iodide from the nitride complex [(PPhP2Cy)Mo(N)(I)] to generate the corresponding cationic complex [(PPhP2Cy)Mo(N)]+ followed by addition of the bis‐silane. Addition of PMe3 to the [(PPhP2Cy)Mo(H)2(NSiMe2CH2CH2SiMe2)]+ complex liberates the silylamine and forms the Mo(II) cationic complex [(PPhP2Cy)Mo(H)(PMe3)]+. DFT calculations rationalizing the observed reactivity are presented. [ABSTRACT FROM AUTHOR]