Nitrogen-carbon bond-forming reactions at coordinated dinitrogen in a bifunctional titanium-potassium system are reported. A titanium atrane complex with a tris(aryloxide)methyl ligand (1) was treated with two equivalents of potassium naphthalenide under N atmosphere to generate a bifunctional complex (2) in which N binds end-on to two titanium centers and side-on to three potassium cations. Dinitrogen complex 2 reacted with carbon dioxide, tert-butyl isocyanate, and phenylallene, forming nitrogen-carbon bonds and affording diverse N-functionalized products. The reaction of 2 with CO followed by addition of Me SiCl resulted in the formation of the starting complex 1 with concomitant release of silylated carboxyl hydrazines while the reaction with two equivalents of tert-butyl isocyanate proceeded by insertion into the Ti-N bonds. Treatment of 2 with phenylallene afforded vinyl-substituted hydrazido complexes.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1002/anie.201704286 | DOI Listing |
Carbohydr Polym
July 2022
Innovation Center for Textile Science and Technology, Co-innovation Center for Textile Industry, Donghua University, Shanghai 201620, China. Electronic address:
Cellulose-based fabrics with suitably high hydrophobicity and good air-permeability are highly promising for disposable hygiene applications. Herein, a facile, one-step method is reported, which effectively converts the completely hydrophilic cellulose nonwoven substrate into highly hydrophobic fabrics (water contact angle of 130-135°) with preservation of a good air-permeability (variation ± 6% after modification compared to the original 1337 mm·s). Mono-isocyanates with bulky, hydrophobic moieties were adopted and 3-isocyanatopropyltrimethoxysilane (ISPTMOS) was found to be the most efficient one compared to tert-butyl isocyanate (TBIS) and m-toluene isocyanate (MTIS).
View Article and Find Full Text PDFDalton Trans
March 2019
Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106 Braunschweig, Germany.
The half-sandwich 1,3-bis(trimethylsilyl)allyl and bis(trimethylsilyl)amido ruthenium complexes [(η5-C5Me5)RuX] (X = η3-C3H3(SiMe3)2, 1; X = N(SiMe3)2, 2) were prepared by reaction of tetranuclear [(η5-C5Me5)RuCl]4 with four equivalents of K[C3H3(SiMe3)2] or Na[N(SiMe3)2]. Complexes 1 and 2 are formally 16- and 14-electron complexes, respectively, and exhibit γ-agostic C-HRu interactions in the solid state, which were further investigated by density functional theory (DFT) calculations and quantum theory of atoms in molecules (QTAIM) analysis. The acid-base reaction of the amido complex 2 with 1,3-bis(2,6-diisopropylphenyl)imidazolin-2-imine (ImDippNH) afforded the imidazolin-2-iminato complex [(η5-C5Me5)Ru(NImDipp)] (4); 4 was also obtained from the reaction of [(η5-C5Me5)RuCl]4 with the lithium reagent [(ImDippN)Li]2.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
July 2017
Department of Chemistry, Tokyo Institute of Technology, Ookayama, Meguro-ku, Tokyo, 152-8551, Japan.
Nitrogen-carbon bond-forming reactions at coordinated dinitrogen in a bifunctional titanium-potassium system are reported. A titanium atrane complex with a tris(aryloxide)methyl ligand (1) was treated with two equivalents of potassium naphthalenide under N atmosphere to generate a bifunctional complex (2) in which N binds end-on to two titanium centers and side-on to three potassium cations. Dinitrogen complex 2 reacted with carbon dioxide, tert-butyl isocyanate, and phenylallene, forming nitrogen-carbon bonds and affording diverse N-functionalized products.
View Article and Find Full Text PDFDalton Trans
May 2015
Technische Universität Braunschweig, Institut für Anorganische und Analytische Chemie, Hagenring 30, 38106 Braunschweig, Germany.
The reaction of the N-heterocyclic carbene 1,3-di-tert-butyl-4,5-dimethylimidazolin-2-ylidene () with trimethylsilyl iodide, triflate and triflimidate [Me3SiX, X = I, CF3SO3 (OTf), (CF3SO2)2N (NTf2)] by mixing the neat, liquid starting materials afforded the corresponding 2-(trimethylsilyl)imidazolium salts [()SiMe3]X as highly reactive, white crystalline solids. Only the triflimidate (X = NTf2) proved to be stable in solution and could be characterized by means of NMR spectroscopy (in C6D5Br) and X-ray diffraction analysis, whereas dissociation into free and Me3SiOTf was observed for the triflate system, in agreement with the trend derived by DFT calculations; the iodide was too insoluble for characterization. The compounds [()SiMe3]X showed the reactivity expected for frustrated carbene-silylium pairs, and treatment with carbon dioxide, tert-butyl isocyanate and diphenylbutadiyne gave the 1,2-addition products [()CO2SiMe3]X (X = I, OTf, NTf2), [()C(NtBu)OSiMe3]OTf and [()C(Ph)C(SiMe3)CCPh]OTf, respectively.
View Article and Find Full Text PDFDalton Trans
August 2012
Institut für Anorganische und Analytische Chemie, Technische Universität Carolo-Wilhelmina, Hagenring 30, D-38106 Braunschweig, Germany.
The bifunctional frustrated Lewis pair 1-[bis(pentafluorophenyl)boryl]-3,5-di-tert-butyl-1H-pyrazole (1) was employed for small molecule fixation by reaction with carbon dioxide, paraformaldehyde, tert-butyl isocyanate, tert-butyl isothiocyanate, methyl isothiocyanate and benzonitrile, affording the adducts 3-8 as zwitterionic, bicyclic boraheterocycles. Treatment of 1 with tert-butyl isocyanide gave the isocyanide-borane complex 9, whereas the zwitterionic alkynylborate 10 was formed by C-H bond activation of phenylacetylene. The molecular structures of all products 3-10 were established by X-ray diffraction analyses.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!