Synthesis and Characterization of Tungsten Alkylidene and Alkylidyne Complexes Supported by a New Pyrrolide-Centered Trianionic ONO3– Pincer-Type Ligand
摘要:
Synthetic protocols for a pyrrolide-centered ONO3- trianionic pincer-type ligand are presented. Treating ((BuO)-Bu-t)(3)W equivalent to(CBu)-Bu-t with the proligand [pyr-ONO]H-3 (2) results in the formation of the trianionic pincer alkylidene complex [pyr-ONO]W=(CHBu)-Bu-t((OBu)-Bu-t) (3). Addition of a mild base to complex 3 provides the trianionic pincer alkylidyne complex {MePPh3}{[pyr-ONO]W equivalent to(CBu)-Bu-t((OBu)-Bu-t)} (4). All new compounds were characterized by NMR spectroscopy, combustion analysis, and, in the case of complex 4, single-crystal X-ray crystallography. D FT calculations performed on 4 provide insight into its electronic structure and indicate that the HOMO is ligand-based and localized on the pyrrolide pi orbitals.
ONO PINCER LIGANDS AND ONO PINCER LIGAND COMPRISING METAL COMPLEXES
申请人:UNIVERSITY OF FLORIDA RESEARCH FOUNDATION, INC.
公开号:US20140073800A1
公开(公告)日:2014-03-13
Embodiments of the invention are directed to ONO pincer ligands that can be in a trianionic, protonated or protonated equivalent form. The ONO pincer ligand can be combined with a transition metal comprising compound to form an ONO pincer ligand comprising transition metal complex. By choice of the ONO pincer ligand structure, the steric and electronic properties of the transition metal complexes therefrom can be controlled. The ONO pincer ligands comprise a central nitrogen atom that is disubstituted with a pair of three atom comprising bridges where the three atoms are three sp
2
hybridized carbons or the three atoms are a pair of sp
2
hybridized carbons and an sp
3
hybridized carbon or silicon.
Synthesis and Stereochemical Properties of âExtendedâ Biphenols Bridged by<i>ortho</i>-,<i>meta</i>-, and<i>para</i>-Phenylene Spacers
作者:Mariusz M. Gruza、Jean-Claude Chambron、Enrique Espinosa、Emmanuel Aubert
DOI:10.1002/ejoc.200900837
日期:2009.12
A series of isomeric biphenols based on para- (1), meta- (2), and ortho- (3) terphenyl backbones was synthesized. Suzuki cross-coupling methodology was employed for the construction of the terphenyl backbone of their methyl-protected precursors (respectively 8, 13, and 16). Using K2CO3 as the base, the best reaction conditions involved DMF at 100 °C as solvent. Anhydrous conditions greatly improved
Synthesis and Characterization of Tungsten Alkylidene and Alkylidyne Complexes Supported by a New Pyrrolide-Centered Trianionic ONO<sup>3–</sup> Pincer-Type Ligand
作者:Matthew E. O’Reilly、Soufiane S. Nadif、Ion Ghiviriga、Khalil A. Abboud、Adam S. Veige
DOI:10.1021/om4009422
日期:2014.2.24
Synthetic protocols for a pyrrolide-centered ONO3- trianionic pincer-type ligand are presented. Treating ((BuO)-Bu-t)(3)W equivalent to(CBu)-Bu-t with the proligand [pyr-ONO]H-3 (2) results in the formation of the trianionic pincer alkylidene complex [pyr-ONO]W=(CHBu)-Bu-t((OBu)-Bu-t) (3). Addition of a mild base to complex 3 provides the trianionic pincer alkylidyne complex MePPh3}[pyr-ONO]W equivalent to(CBu)-Bu-t((OBu)-Bu-t)} (4). All new compounds were characterized by NMR spectroscopy, combustion analysis, and, in the case of complex 4, single-crystal X-ray crystallography. D FT calculations performed on 4 provide insight into its electronic structure and indicate that the HOMO is ligand-based and localized on the pyrrolide pi orbitals.