Reactions of the group 4 metallocene alkyne complexes [Cp'2 M(η(2) -Me3 SiC2 SiMe3 )] [Cp'2 =rac-(ebthi)=rac-1,2-ethylene-1,1'-bis(η(5) -tetrahydroindenyl): M=Ti, Zr, Hf; Cp'2 =Cp*2 (Cp*=η(5) -pentamethylcyclopentadienyl): M=Zr] with 2,6-dimethylphenyl isocyanide (2-xylyl isonitrile, XyNC) were investigated. Depending on the metal, the Cp' ligand, and/or the stoichiometry, as well as the reaction temperature and time, different products were obtained. The products included simple end-on coordination compounds of XyNC in addition to those of the coupling of Me3 SiC2 SiMe3 with two, three, or four isonitriles to form enimine complexes, aza-metallacycloallenes, and fused heterocyclic systems, respectively. One example of the latter tricyclic compounds was subject to demetalation by using HCl. Molecular structures of the heterometallacycles were determined by X-ray crystallography. The interconversion of the products was investigated by (1) H NMR spectroscopy.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1002/chem.201601465 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Latest News: Reactions of Group 4 Bis(trimethylsilyl)acetylene Metallocene Complexes and Applications of the Obtained Products.
ChemistryOpen
December 2021
Leibniz Institute for Catalysis at the, University of Rostock, Albert-Einstein-Str. 29 A, 18059, Rostock, Germany.
Recently published reactions of group 4 metallocene bis(trimethylsilyl)acetylene (btmsa) complexes from the last two years are reviewed. Complexes like Cp' Ti(η -Me SiC SiMe ) and Cp Zr(py)(η -Me SiC SiMe ) with Cp' as Cp (cyclopentadienyl) and Cp* (pentamethylcyclopentadienyl) have been considered (py=pyridine). These complexes can liberate a reactive low-valent titanium or zirconium center by dissociation of the ligands and act as ''masked'' M complexes (M=Ti, Zr).
View Article and Find Full Text PDFPlanar Tetracoordinated Silicon (ptSi): Room-Temperature Stable Compounds Containing Anti-van't Hoff/Le Bel Silicon.
J Am Chem Soc
January 2021
Institute of Inorganic Chemistry, University of Bonn, Gerhard-Domagk-Straße 1, D-53121 Bonn, Germany.
While a variety of compounds containing planar tetracoordinated carbon (ptC), the so-called anti-van't Hoff/Le Bel carbon, are known experimentally, stable systems containing planar tetracoordinated silicon (ptSi) are barely known. As part of our studies on the application of stereoelectronically well-defined transition-metal fragments to stabilize silicon in unprecedented bonding modes, we report herein the synthesis and full characterization of a series of thermally stable complexes of the general formula [Tp'(CO)MSiC(R)C(R)M(CO)Tp'] (M = Mo, W; R = R = Me or R = H, R = SiMe, Ph; Tp' = κ-,',″-hydridotris(3,5-dimethylpyrazolyl)borate), which incorporate a ptSi atom in addition to two ptC atoms. The complexes were obtained by reacting the metallasilylidyne complexes [Tp'(CO)M≡Si-M(CO)(PMe)Tp'] with alkynes RC≡CR and were comprehensively analyzed by experimental studies and quantum chemical calculations.
View Article and Find Full Text PDFReactions of Group 4 Metallocene Bis(trimethylsilyl)acetylene Complexes with Nitriles and Isonitriles.
Angew Chem Int Ed Engl
November 2018
Leibniz Institute for Catalysis at the, University of Rostock, Albert-Einstein-Strasse 29A, 18059, Rostock, Germany.
This Review summarizes reactions of Group 4 metallocene bis(trimethylsilyl)acetylene complexes with nitriles and isonitriles. Selected examples of reactions of Group 4 metallocene alkyne complexes of the type Cp' M(η -Me SiC SiMe ) with different nitriles and isonitriles are described following the general L-M-S principle, in which stoichiometric and catalytic reactions are influenced by ligands L, metals M, and substrate substituents S. The influence of all these parameters is highlighted.
View Article and Find Full Text PDFTitanocene Silylpropyne Complexes: Promising Intermediates en route to a Four-Membered 1-Metallacyclobuta-2,3-diene?
Chemistry
October 2017
Leibniz-Institut für Katalyse e.V. an der Universität Rostock, Albert-Einstein-Str. 29a, 18059, Rostock, Germany.
Coordination of the alkyl-substituted alkynes Me SiC CH R (1: R=SiMe ; 2: R=N(SiMe ) ) to titanocene centres [Cp' Ti] (Cp'=Cp, Cp*) yields stable alkyne complexes of the type Cp' Ti(η -Me SiC CH R) (3: Cp'=Cp, R=SiMe ; 5: Cp'=Cp, R=N(SiMe ) ; 6: Cp'=Cp*, R=SiMe ) that are not prone to alkyne/allene isomerisation. When reacting alkyne 2 with Cp TiCl and Mg formation of the complex Cp* Ti(III)(η -Me SiC CH ) (7) which displays a propargylic unit coordinated to the Ti centre takes place. All complexes were fully characterised, the molecular structures for 5, 6, and 7 are discussed.
View Article and Find Full Text PDFMultiple and Highly Selective Alkyne-Isonitrile C-C and C-N Couplings at Group 4 Metallocenes.
Chemistry
June 2016
Leibniz-Institut für Katalyse e.V. an der, Universität Rostock, Albert-Einstein-Straße 29a, 18059, Rostock, Germany.
Reactions of the group 4 metallocene alkyne complexes [Cp'2 M(η(2) -Me3 SiC2 SiMe3 )] [Cp'2 =rac-(ebthi)=rac-1,2-ethylene-1,1'-bis(η(5) -tetrahydroindenyl): M=Ti, Zr, Hf; Cp'2 =Cp*2 (Cp*=η(5) -pentamethylcyclopentadienyl): M=Zr] with 2,6-dimethylphenyl isocyanide (2-xylyl isonitrile, XyNC) were investigated. Depending on the metal, the Cp' ligand, and/or the stoichiometry, as well as the reaction temperature and time, different products were obtained. The products included simple end-on coordination compounds of XyNC in addition to those of the coupling of Me3 SiC2 SiMe3 with two, three, or four isonitriles to form enimine complexes, aza-metallacycloallenes, and fused heterocyclic systems, respectively.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!