Ruthenium Olefin Metathesis Initiators Bearing Chelating Sulfoxide Ligands

Abstract

New ruthenium olefin metathesis initiators bearing sulfoxide moieties are described. The complexes were synthesized by the reaction of indenylidene ruthenium complexes Ind-II and Ind-II′ with different (2-vinyl)phenyl sulfoxides. These compounds show no catalytic activity at room temperature, but exhibit increased activity at elevated temperature. Preliminary studies on the influence of electronic and steric factors on the catalytic activity are presented.

A Study of Factors Affecting Enantioselectivity in the Oxidation of Aryl Benzyl Sulfides in the Presence of Chiral Titanium Catalysts

“…The ee value for sulfoxide 1b [13] was measured by HPLC (column: Chiralcel OD-H; eluent: nhexane/2-propanol, 90:10). [35] M.p. 53-54°C.…”

“…C 42.30, H 1.64; found C 42.39, H 1.90. [35] Prepared by reacting iodobenzene and 2-bromothiophenol in the presence of potassium carbonate and copper iodide in NMP according to a reported procedure. [36] Kugelrohr oven temp.…”

Non-nucleoside Inhibitors of the Measles Virus RNA-Dependent RNA Polymerase: Synthesis, Structure–Activity Relationships, and Pharmacokinetics

“…Unsubstituted phenyl analog 3a was found to be as active as lead compound 2 triggering an SAR study of the series (Table 2). Coupling of 2-methoxylthiophenol 16a with 1-fluoro-4-nitrobenzene 18 followed by oxidation of sulfur using MCPBA gave corresponding sulfone, which went through reduction of the nitro group and followed by coupling with acid chloride 8 furnished analog 3b . Demethylation of 3b with BBr 3 afforded phenol analog 3c , which on acylation gave analog 3d .…”

Chelating Ruthenium Phenolate Complexes: Synthesis, General Catalytic Activity, and Applications in Olefin Metathesis Polymerization

“…[3,4] To solve this problem, a number of latent Ru-catalysts have been developed in recent years. [5] The use of such catalysts in ROMP allows for the catalyst to be mixed with the monomer with no polymerization at RT, in order to give enough time to handle the formulation. Once required, the catalyst can be acti-vated by chemical or physical methods.…”

“…In addition, such latent catalysts shall exhibit high solubility in a monomer (no co-solvent needed) and high thermal stability. [5] The few Ru catalysts that amply fulfill these prerequisites, and have been successfully used in ROMP of DCPD, are complexes bearing bidentate Schiff base ligands (e.g., 2 and 3 in Figure 1). [6] Recently, we reported the synthesis of chelating ruthenium sulfonamides (4, Figure 2), [7a] a new family in the kingdom of ruthenium-based metathesis catalysts bearing altered anionic ligands.…”