Access to Unsaturated Ruthenium Complexes via Phosphine Complexation with Triphenylborane:  Synthesis and Structure of a Zwitterionic Arene Complex, (η⁶-Ph-BPh₂H)Ru(PMe₃)₂(SiMe₃)

Abstract

Triphenylborane, BPh 3 , serves as a phosphine "sponge", scavenging free PMe 3 from alkane solutions of the 18ecomplex (PMe 3 ) 4 Ru(SiMe 3 )H to form sparingly soluble Ph 3 B-PMe 3 and the 16e -(PMe 3 ) 3 Ru(SiMe 3 )H. Under nitrogen atmosphere the 16e -(PMe 3 ) 3 Ru(SiMe 3 )H forms a dimeric N 2 adduct, [(PMe 3 ) 3 Ru(SiMe 3 )H] 2 N 2 . Both the 16ecomplex and its N 2 adduct exist in equilibrium with the 18esilene complex, (PMe 3 ) 3 Ru(CH 2 dSiMe 2 )H 2 . However, long reaction times in the presence of excess borane leads to removal of another phosphine ligand as Ph 3 B-PMe 3 and formation of a new zwitterionic complex, (η 6 -PhBPh 2 H)Ru(PMe 3 ) 2 (SiMe 3 ) (5), in which a molecule of borane has abstracted a ruthenium hydride ligand and also coordinates as an η 6 -arene. The merits and limitations of BPh 3 as a phosphine removal agent are discussed. Compound 5 has been characterized by single-crystal X-ray analysis and exhibits unusually long Ru-C arene bonds.

Tandem β‐CH Activation/SiH Elimination Reactions: Stabilization of CH Activation Products by β‐Agostic SiH Interactions

“…Treatment of a mixture of the 16‐electron [(Me 3 P) 3 Ru(SiMe 3 )H], in equilibrium with the “silene dihydride” complex [(Me 3 P) 3 Ru(η 2 ‐CH 2 SiMe 2 )(H) 2 ] ( 1 )4a,b with CHCl 3 between −40 and 0 °C leads to the chlorination of one hydride and the formation of [(Me 3 P) 3 Ru(CH 2 SiMe 2 )(H)Cl], fac ‐( 2 ) [Eq. (2)], which has been isolated in 86 % yield and fully characterized.…”

Zwitterionische Verwandte kationischer Platinmetallkomplexe: Anwendungen in der stöchiometrischen und katalytischen σ‐Bindungsaktivierung

“…Die vorgeschlagene Verknüpfung in 2 und ähnlichen Rh‐ und Ir‐Derivaten (einschließlich des η 4 ‐1,5‐Cyclooctadien‐Analogons 3 ) beruht auf IR‐ und NMR‐spektroskopischen Daten16 und wurde durch die kristallographische Charakterisierung von 4 bestätigt 17. In den folgenden Jahren wurde über zahlreiche andere ein‐, zwei‐, drei‐ und vierkernige Metallkomplexe der 8 18–26. und 9.…”

MOLECULAR STRUCTURE OF ORGANOSILICON COMPOUNDS WITH Si - Ru, Si - Rh and Si - Pd BONDS

“…?7 5 -Cyclopentadienyl (Cp) and rj 5 -pentamethylcyclopentadienyl (Cp*) derivatives 1 [3][4][5][6][7] as well as rj 6 -arene complexes 2-4 [8][9][10] adopt a three-legged piano stool geometry around ruthenium with legs composed of silyl and carbonyl or trimethylphosphine groups. The Ru -Si bond distance in trichlorosilyl complex 1 (Cp, L=Me 3 P) of 2.265 A, is consistent with a single bond.…”