title: Diaryl sulfoxides from aryl benzyl sulfoxides: a single palladium-catalyzed triple relay process.
abstract: A novel approach to produce diaryl sulfoxides from aryl benzyl sulfoxides is reported. Optimization of the reaction conditions was performed using high-throughput experimentation techniques. The [Pd(dba)2 ]/NiXantPhos catalyst system successfully promotes a triple relay process involving sulfoxide α-arylation, CS bond cleavage, and CS bond formation. The byproduct benzophenone is formed by an additional palladium-catalyzed process. It is noteworthy that palladium-catalyzed benzylative CS bond cleavage of sulfoxides is unprecedented. A wide range of aryl benzyl sulfoxides, as well as alkyl benzyl sulfoxides with various (hetero)aryl bromides were employed in the triple relay process in good to excellent yields (85-99 %). Moreover, aryl methyl sulfoxides, dibenzyl sulfoxides, and dimethylsulfoxide could be utilized to generate diaryl sulfoxides involving multiple catalytic cycles by a single catalyst.
authors.affiliation: Roy and Diana Vagelos Laboratories, Penn/Merck Laboratory for High-Throughput Experimentation, Department of Chemistry, University of Pennsylvania, 231 S. 34th St. Philadelphia, PA 19104-6323 (USA) http://titanium.chem.upenn.edu/walsh/
authors.forename: Tiezheng
authors.initials: T
authors.lastname: Jia
authors.forename: Ana
authors.initials: A
authors.lastname: Bellomo
authors.forename: Sonia
authors.initials: S
authors.lastname: Montel
authors.forename: Mengnan
authors.initials: M
authors.lastname: Zhang
authors.forename: Kawtar
authors.initials: K
authors.lastname: El Baina
authors.forename: Bing
authors.initials: B
authors.lastname: Zheng
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Walsh
mesh_terms: D001965:Bromides / Q000737:chemistry*; D002384:Catalysis; D015394:Molecular Structure; D010165:Palladium / Q000737:chemistry*; D013454:Sulfoxides / Q000737:chemistry*
chemical_list: D001965:Bromides; D013454:Sulfoxides; D010165:Palladium
keywords: SO compounds; cross-coupling; homogeneous catalysis; palladium; synthetic methods