212792-19-3Relevant academic research and scientific papers
An Amidinate Ligand with a Pendant Amine Functionality; Synthesis of a Vanadium(III) Complex and Ethene Polymerization Catalysis
Brandsma, Menno J. R.,Brussee, Edward A. C.,Meetsma, Anke,Hessen, Bart,Teuben, Jan H.
, p. 1867 - 1870 (2008/10/08)
A new type of amidinate ancillary ligand has been prepared, which incorporates a pendant tertiary amine functionality. The crystal structure of a vanadium(III) derivative, [SiMe3NC(Ph)NCH2CH2NMe2]VCl 2(THF) (1), shows that the ligand can adopt a facial geometry, with an unusual distortion of the amidinate nitrogen bearing the pendant functionality. With AlEt2Cl cocatalyst the compound 1 produces a single-site catalytic system for the polymerization of ethene.
Electron-deficient vanadium(III) alkyl and allyl complexes with amidinate ancillary ligands
Brussee, Edward A. C.,Meetsma, Auke,Hessen, Bart,Teuben, Jan H.
, p. 4090 - 4095 (2008/10/08)
Vanadium(III) amidinate complexes (amidinate)2VCl and (amidinate)VCl2(THF)2 were prepared for two different amidinate ligands, [PhC(NSiMe3)2]- and [t-BuC(Ni-Pr)2]-. These served as precursors for amidinate V(III) alkyl and allyl derivatives. The allyl ligand in (amidinate)2V(allyl) is η3-bound, indicating that the amidinates act as four-electron anionic ligands. The 12-electron alkyl complex [PhC(NSiMe3)2]2VMe catalyzes the slow oligomerization of ethene to linear olefins at 80°C. The bis-allyl complex [t-BuC(Ni-Pr)2]V(η3-allyl)2 was prepared and structurally characterized, but its analogue with the [PhC(NSiMe3)2] ligand already decomposes around -30°C. This shows that the substituent pattern of the amidinate ancillary ligand can strongly affect the stability of organometallic derivatives.
