Poly(imidazolyliden-yl)borato Complexes of Tungsten: Mapping Steric vs. Electronic Features of <i>Facially</i> Coordinating Ligands
oleh: Callum M. Inglis, Richard A. Manzano, Ryan M. Kirk, Manab Sharma, Madeleine D. Stewart, Lachlan J. Watson, Anthony F. Hill
| Format: | Article |
|---|---|
| Diterbitkan: | MDPI AG 2023-11-01 |
Deskripsi
A convenient synthesis of [HB(HImMe)<sub>3</sub>](PF<sub>6</sub>)<sub>2</sub> (ImMe = <i>N</i>-methylimidazolyl) is decribed. This salt serves in situ as a precursor to the tris(imidazolylidenyl)borate Li[HB(ImMe)<sub>3</sub>] pro-ligand upon deprotonation with <i><sup>n</sup></i>BuLi. Reaction with [W(≡CC<sub>6</sub>H<sub>4</sub>Me-4)(CO)<sub>2</sub>(pic)<sub>2</sub>(Br)] (pic = 4-picoline) affords the carbyne complex [W(≡CC<sub>6</sub>H<sub>4</sub>Me-4)(CO)<sub>2</sub>{HB(ImMe)<sub>3</sub>}]. Interrogation of experimental and computational data for this compound allow a ranking of familiar tripodal and facially coordinating ligands according to steric (percentage buried volume) and electronic (ν<sub>CO</sub>) properties. The reaction of [W(≡CC<sub>6</sub>H<sub>4</sub>Me-4)(CO)<sub>2</sub>{HB(ImMe)<sub>3</sub>}] with [AuCl(SMe<sub>2</sub>)] affords the heterobimetallic semi-bridging carbyne complex [WAu(μ-CC<sub>6</sub>H<sub>4</sub>Me-4)(CO)<sub>2</sub>(Cl){HB(ImMe)<sub>3</sub>}].