- Synthesis, characterization and structures of diphenyldiaminosilanes bearing bulky substituents on nitrogen
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Aminosilanes bearing bulky substituents on nitrogen centers, [(ArNH)2SiPh2] (Ar=2,6-iPr2C6H3 (1), 2,4,6-Me3C6H2 (2), 2,6-Et2C6H3 (3)), have been prepared in good yields by the addition of dichlorodiphenylsilane to the corresponding substituted monolithiated aniline. The new compounds have been characterized by elemental analysis and IR, EI mass and NMR (1H and 29Si) spectroscopic studies. The solid-state structures of 1 and 3 have been determined by single crystal X-ray diffraction studies. The molecules have a Cs symmetry and the two N-H protons are approximately trans to each other. The amido nitrogen atoms show significant deviation from trigonal-planar geometry, as a result of which the observed Si-N bonds are marginally longer than those observed in aminosilanes with planar nitrogen atoms.
- Murugavel, Ramaswamy,Palanisami, Nallasamy,Butcher, Ray J.
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- Low-cost condition iron compound synthesis
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The invention discloses a ligand capable of stabilizing a low-valence state iron compound and two compounds containing iron ions of two different valence states, and belongs to the chemical field of organic metal materials. The compound containing a Fe(I)-Fe(I) metal bond has good ferromagnetism. The compounds are more difficult to synthesize, so that research on molecular magnets in the field is little. Meanwhile, the compound containing low-valence state Fe(I)-Fe(I) metal bond has potential application in biological and inorganic fields such as carbon monoxide/ dehydrogenase catalytic cycle, nitrogen gas activation, and the like, so that the research in the field is very important.
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Paragraph 0026-0030
(2017/09/01)
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- Alkaline-Earth-Catalysed Cross-Dehydrocoupling of Amines and Hydrosilanes: Reactivity Trends, Scope and Mechanism
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Alkaline-earth (Ae=Ca, Sr, Ba) complexes are shown to catalyse the chemoselective cross-dehydrocoupling (CDC) of amines and hydrosilanes. Key trends were delineated in the benchmark couplings of Ph3SiH with pyrrolidine or tBuNH2. Ae{
- Bellini, Clément,Dorcet, Vincent,Carpentier, Jean-Fran?ois,Tobisch, Sven,Sarazin, Yann
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p. 4564 - 4583
(2016/03/22)
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- Probing the metallating ability of a polybasic sodium alkylmagnesiate supported by a bulky bis(amido) ligand: Deprotomagnesiation reactions of nitrogen-based aromatic substrates
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Exploring the reactivity of sodium butylmagnesiate reagent [{Na(THF) 6}+{(Ph2Si(NAr*)2)Mg(Bu)(THF)} -] (1) supported by the bulky chelating silyl(bisamido) ligand {Ph2Si(NAr*)2}2- (Ar* = 2,6-iPr2-C6H3) towards N-methylbenzimidazole (bImMe), pyrrole and 2,6-diisopropylaniline (NH2Ar*) , this study provides new insights into the ability of this bimetallic base to facilitate direct Mg-H exchange reactions as well as to exhibit polybasicity. Thus 1 effectively promotes the deprotomagnesiation of bImMe under mild reaction conditions to give the α-metallated intermediate [{Na(THF)5}2+{(Ph2Si(NAr*) 2)Mg(bImMe*)}2-] (2) (bIm Me* = 2-N-methylbenzimidazolyl). Analysis of crystallographic and NMR data of 2 combined with DFT calculations show that the metallated C in the bImMe* ligands possesses a significant carbenic character. Contrasting with previous studies of benzothiazole (btz), 1 does not react with an excess of bImMe even under forcing refluxing conditions. Contrastingly, the amination reactions of equimolar amounts of 1 with pyrrole and 2,6-diisopropylaniline allowed the isolation of [{(Ph 2Si(NAr*)(NHAr*))Mg(NC4H4) 2(THF)Na(THF)2}] (3) and [{Na(THF)6} +{(Ph2Si(NAr*)(NHAr*))Mg(NHAr*) 2(THF)}-] (4) respectively as crystalline solids. Highlighting the ability of 1 to act as a polybasic reagent, 3 and 4 are formed as the result of the deprotonation of two molecules of the relevant amine via its butyl group and one amido arm of the silyl(bisamido) ligand. Similarly, the reactions of 1 with 3 molar equivalents of the relevant amine yielded homoleptic tris(amido) compounds [(THF)2NaMg(NC4H4) 3] (5) and [{Na(THF)6}+{Mg(NHAr*) 3}-] (7), with the concomitant formation of bis(amine) Ph2Si(NHAr)2, as a result of the complete amination of 1 using its three basic sites. The structures in the solid state of 3 and 4 were elucidated by X-ray crystallography. Despite their similar constitution, these heteroleptic tris(amido)magnesiates adopt contrasting structures, with the former displaying a contacted ion-pair structure, where Na and Mg are connected by two bridging pyrrolyl anions, whereas the latter gives rise to a solvent-separated ion pair motif. To the best of our knowledge 3 represents the first crystallographically characterized magnesium compound containing an anionic non-substituted form of pyrrole. Noticeably, Mg interacts exclusively with the N atoms of the pyrrolyl ligands, forming strong σ-bonds, whereas Na prefers to engage with the π-systems of both NC4-rings.
- Armstrong, David R.,Clegg, William,Hernan-Gomez, Alberto,Kennedy, Alan R.,Livingstone, Zoe,Robertson, Stuart D.,Russo, Luca,Hevia, Eva
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supporting information
p. 4361 - 4369
(2014/03/21)
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- Magnesium-mediated benzothiazole activation: A room-temperature cascade of C-H deprotonation, C-C coupling, ring-opening, and nucleophilic addition reactions
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Ligand domin(o)ated: In contrast to the straightforward deprotonation of benzothiazole using Grignard reagents, treatment of benzothiazole with 1 leads to a novel type of activation. The initial magnesiation initiates an unstoppable domino reaction of C-C coupling, ring opening, nucleophilic addition, and deprotonation to give 2. THF=tetrahydrofuran. Copyright
- Blair, Victoria L.,Clegg, William,Kennedy, Alan R.,Livingstone, Zoe,Russo, Luca,Hevia, Eva
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supporting information; experimental part
p. 9857 - 9860
(2011/11/29)
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