Di‐tert‐Butyl Peroxide‐Mediated Atom‐Transfer Radical Addition of 2‐Chlorodithiane to Aryl Alkynes under Mild Conditions

Abstract

Atom transfer radical addition (ATRA) of 2-chlorodithiane onto aryl alkynes through the use of di-tert-butyl peroxide as an oxidant at room temperature directly affords a variety of synthetically valuable β-chloro-(Z)-vinyl dithianes in good yields with high regioselectivities and without the assistance of any transition metals. It provides an operationally simple pathway to access vinyl dithianes with controlled formation of a new C(sp(2) )C bond and a C(sp(2) )Cl bond.

Silver-catalyzed synthesis of β-fluorovinylphosphonates by phosphonofluorination of aromatic alkynes

“…and Ag(II)F. The electrophilic phosphonyl radical addition to the triple bond of 1a generates the vinyl-free radical INT-II, which is subsequently trapped by AgF(II) to afford the corresponding product 2a. The vinyl radical INT-II stabilizes the unpaired electron through resonance, and INT-II is more stable than INT-III [27,28]. Finally, we obtained the Z-configured product with respect to the aryl and phosphonyl groups.…”

Dithiane-Induced [3+2] Cycloaddition Tactic for the Convergent Synthesis of Dihydropyrrole and Pyrrole Derivatives

“…Our previous investigations proposed that the desired vinyl dithiane intermediate could be generated from β-chloro-alkenyl dithianes in the presence of a base . Likewise, we investigated our initial screening experiments by exploring the cycloaddition of the corresponding dithiane 1a with readily available imines (Scheme ).…”

“…In many instances, [3+2] cycloaddition reactions between two substituents originating from simple starting materials provide an efficient and divergent synthesis of highly substituted pyrroles . We have recently disclosed a 1,3-dipolar cycloaddition of β-chloro-vinyl dithianes with a variety of related aldehydes and unsaturated carbonyl compounds that provide convenient access to the regioselective synthesis of cycloadduct derivatives . Our previous work demonstrated the examples of ambivalent electrophilic and nucleophilic reactivity modes of vinylidene dithiane species.…”

Copper-Catalyzed Cascade Radical Addition–Cyclization Halogen Atom Transfer between Alkynes and Unsaturated α-Halogenocarbonyls

“…Yet, methods for the synthesis of cyclic systems through an intermolecular ATRC process are lacking. , As a result, the application scope of ATRC has been restricted. Moreover, some progress has been also been made in the intermolecular ATRA reactions between alkyl halides and alkynes . Recently, Hu reported a Cu-catalyzed cis-selective carboiodination of terminal acetylenes with functionalized alkyl iodides, which were generated by treating alkyl bromides with KI (Scheme a).…”