Hoveyda‐Type Olefin Metathesis Complexes

In a Quest for Selectivity Paired with Activity: A Ruthenium Olefin Metathesis Catalyst Bearing an Unsymmetrical Phenanthrene‐Based N‐Heterocyclic Carbene

“…[21] One of the strategies affording ruthenium complexes with fine-tuned selectivity is modification of NHC. [3,[22][23][24][25][26][27] This hasl ed to increasing interest in the use of various unsymmetrical NHC (uNHC) ligandsi nolefin metathesis (Figure 1). [28,29] One of the earliest mentions of N-alkyl-N'-aryl NHC based ruthenium complexes, are catalysts published by the Blechert (Figure 1, L4-C) [30] and Verpoort groups (Figure 1, L5-A,C).…”

Photoactivation of Ruthenium Phosphite Complexes for Olefin Metathesis

“…A notable series of precatalysts that may be photoinitiated is the family of S-chelated ruthenium benzylidenes . These complexes adopt a latent cis -dichloro configuration due to a trans influence repulsion between the strong sigma electron-donating NHC ligand and the chelating sulfur atom . When irradiated with UVA light, isomerization to the active trans dichloro isomer ensues.…”

“…It is also well-known that chelation can promote greater stability in ruthenium benzylidenes . Many efficient chelated ruthenium complexes have been studied in the chemical literature; , however, the use of a phosphite moiety as a chelating agent has not been investigated to date, and there is only one reported P-chelated ruthenium benzylidene in the literature . Thus, a chelating benzylidene phosphite complex ( cis -PhosRu-1 ) was designed and synthesized.…”

The Influence of Various N-Heterocyclic Carbene Ligands on Activity of Nitro-Activated Olefin Metathesis Catalysts

“…Besides varying the NHC ligand, benzylidene ligands offer a broad testing ground for modifications of the catalytic properties of these ruthenium complexes [41]. Our group has developed a nitro-activated version of the Hoveyda complex 4a [42][43][44][45].…”