Unusual Palladium-Catalyzed Cascade Arylation ofα,β-Unsaturated Phenyl Sulfones under Heck Reaction Conditions

Abstract

Four C−C bonds are formed in a single step by an intermolecular four‐component cascade pathway. 1‐Phenyl‐9‐phenylsulfonyl‐9,10‐dihydrophenanthrenes are formed in the palladium‐catalyzed Heck‐like reaction of α,β‐unsaturated phenyl sulfones with three equivalents of iodobenzene in the presence of Ag2CO3 [Eq. (1)].

Supported Palladium Nanoparticles Catalyzed Ortho-Directed C–C Coupling Reaction via a Pd0/PdII/PdIV Catalytic Cycle

“…This suggests that the reaction probably has a radical mechanism. On the basis of the experimental results and the previous reports, ,− a possible mechanism is proposed in Scheme . First, Pd 0 coordinates with the nitrogen atom of the pyridine group of 2-phenylpyridine 1 and Pd 0 is further oxidized to Pd II by air, and subsequently, Pd II activates the ortho C–H bond to generate cyclopalladated intermediate A .…”

Stereoselective Synthesis of Z-α,β-Unsaturated Sulfones Using Peterson Reagents

“…α,β-Unsaturated sulfones are useful substrates in stereospecific reactions for the construction of chiral centers, such as the Michael reaction, epoxidation, and the Heck reaction . In addition, some vinyl sulfones are known as cysteine protease inhibitors and neuroprotective agents for Parkinson’s disease therapy .…”

The Mizoroki‐Heck Reaction with Internal Olefins: Reactivities and Stereoselectivities

“…As was shown in Scheme and , the N,N ‐dimethylamino group was effective as a directing group in the reaction of β‐substituted‐α,β‐unsaturated sulfoxides 18.1 and aryl halides. The Mizoroki‐Heck reaction of β‐substituted‐α,β‐unsaturated sulfones 28.1 possessing an N , N ‐dimethylaniline group gives the corresponding ( E )‐products 28.2 in good yields with perfect selectivities (Scheme ) . An N ‐coordinated palladacycle is generated after arylpalladation of 28.1 to produce ( E )‐ 28.2 exclusively.…”