214754-32-2Relevant academic research and scientific papers
Synthesis of Urea Derivatives from CO2 and Silylamines
Xu, Maotong,Jupp, Andrew R.,Ong, Maegan S. E.,Burton, Katherine I.,Chitnis, Saurabh S.,Stephan, Douglas W.
supporting information, p. 5707 - 5711 (2019/04/16)
A series of thirty-three N,N′-diaryl, dialkyl, and alkyl-aryl ureas have been prepared in pyridine or toluene by reaction of silylamines with CO2. This protocol is shown to provide facile access to 13C-labeled ureas, as well as chiral and macrocyclic ureas. These reactions proceed through initial generation of the corresponding silylcarbamates, which subsequently react with silylamine under thermal conditions to afford the thermodynamically favored urea and disilyl ether.
Synthesis of Group 4 [(RN-o-C6H4)2O]2- complexes where R is SiMe3 or 0.5 Me2SiCH2CH2SiMe2
Schrock, Richard R.,Liang, Lan-Chang,Baumann, Robert,Davis, William M.
, p. 163 - 173 (2007/10/03)
Complexes that contain the [(Me3SiN-o-C6H4)2O]2- ligand ([1]2-) of the type [1]M(NMe2)2, [1]MCl2, and [1]MMe2 have been prepared where M=Ti, Zr, or Hf. Although cations prepared by addition of [Ph3C][B(C6F5)4] or [PhNMe2H][B(C6F5)4] to [1]ZrMe2 or [1]HfMe2 could not be observed in NMR studies, addition of [(η5-C5H4Me)2Fe][B(C 6H5)4] to [1]HfMe2 in the presence of THF led to isolation of {[1]HfMe(THF)2}[B(C6H5)4]. An X-ray study showed the cation to be a distorted octahedron in which the [1]2- ligand is in the mer arrangement and is significantly twisted from a planar NC2OC2N arrangement. The THF ligands are trans to one another. No well-behaved activity for the polymerization of 1-hexene could be observed with activated [1]ZrMe2, while {[1]HfMe(THF)2}[B(C6H5)4] was inactive. The reaction between Li2[O(o-C6H4NH)2] and Me2ClSiCH2CH2SiMe2Cl in THF produced a cyclic diamido/ether ligand H2[2]. The reaction between H2[2] and Zr(NMe2)4 or ZrR4 (R=CH2Ph, CH2SiMe3) gave [2]Zr(NMe2)2(HNMe2) and Zr[2]2, respectively. The dimethylamine in [2]Zr(NMe2)2(HNMe2) could be replaced with pyridine or 2,4-lutidine to give [2]Zr(NMe2)2(L) (L=pyridine or 2,4-lutidine), which then could be converted into [2]ZrCl2(L) with excess Me3SiCl. The reaction between [2]ZrCl2(py) and two equivalents of Me3SiCH2MgCl gave a bimetallic complex in which one of the trimethylsilyl methyl groups has been doubly C-H activated, as confirmed by X-ray crystallography.
