Direct Synthesis of Silylamine from N₂ and a Silane: Mediated by a Tridentate Phosphine Molybdenum Fragment

Abstract

A homogeneous system which is able to yield silylamine from N2 and bis(silane) in one pot is reported. Mechanistically a {(triphosphine)molybdenum(I)} fragment, generated in situ, splits N2 into the corresponding nitrido complex at room temperature. Then, functionalization of the molybdenum nitrido is achieved by double Si-H addition under mild reaction conditions. Moreover, the bis(silyl)amine product is decoordinated from the metal center.

Group 6 Transition‐Metal/Boron Frustrated Lewis Pair Templates Activate N2 and Allow its Facile Borylation and Silylation

“…The 29 Si HMQC NMR spectra of 7 Mo and 7 W give signals at 2.0 and À1.45 ppm for the Si atoms,respectively (vs.0.2 ppm for free Et 3 SiH), which suggests that the positive charge is not located at the Si atom ( Figure S21-25 and S27-31). In dinitrogen-derived hydrazido or nitrido complexes,1 ,2 addition of BÀH [27] or SiÀ H [28] bonds across the MÀNb ond can also be an efficient route to borylation or silylation of dinitrogen; however this necessitates 4or6e À reduction of N 2 by the metal center prior to functionalization. While compound 7 Mo precipitated as an oil, crystals of 7 W suitable for an X-ray diffraction study could be grown, allowing us to validate the proposed structures (Figure 2, right).…”

Group 6 Transition‐Metal/Boron Frustrated Lewis Pair Templates Activate N2 and Allow its Facile Borylation and Silylation

“…5 reaction. In dinitrogen-derived hydrazido or nitrido complexes,1 ,2 addition of BÀH [27] or SiÀ H [28] bonds across the MÀNb ond can also be an efficient route to borylation or silylation of dinitrogen; however this necessitates 4or6e À reduction of N 2 by the metal center prior to functionalization. Mild, alternative routes are disclosed herein, as an onelectrophilic main group hydride is made amenable to react with aw eakly activated N 2 ligand.…”

Dinitrogen‐Molybdenum Complex Induces Dinitrogen Cleavage by One‐Electron Oxidation

“…[6] Thei ntermediates were well characterized, and the catalytic cycle of this reaction was established to be aMo III -Mo VI cycle,which is now known as the Schrock cycle.M any landmark studies of N 2 fixation have also been performed in the development of reactions for catalytic ammonia synthesis in the presence of proton sources and reductants by using transition-metal complexes [1,6,7] Since the direct cleavage of the extremely strong N 2 triple bond (BDE = 226 kcal mol À1 )b yl ow-coordinate and electron-rich transition-metal complexes was first reported by Laplaza and Cummins, [8] investigations of the cleavage of the N 2 triple bond through thermal, chemical, and photochemical reactions have been carried out. Regarding N 2 cleavage by Mo I complexes supported with at ridentate ligand and halogen as intermediates, [1i, [28][29][30] the groups of Schrock, MØzailles,and Nishibayashi have reported that aMo III complex is used as aprecursor for the synthesis of anitride complex. Thereduction of the precursor is promoted by addition of as trong reductant to generate the Mo I complex, and then the Mo IV nitride complex is synthesized by formation of ad imeric Mo complex with ab ridging N 2 molecule in the subsequent reaction.…”