Synthetic Methods for Compounds Having CF3–S Units on Carbon by Trifluoromethylation, Trifluoromethylthiolation, Triflylation, and Related Reactions

This tutorial review is aimed at highlighting recent developments in transition-metal-free carbon–carbon and carbon–heteroatom bond-forming reactions utilizing a versatile class of reactive intermediates, viz., arynes, which hold the potential for numerous applications in organic synthesis. Key to the success of the resurgence of interest in the rich chemistry of arynes is primarily the mild condition for their generation by the fluoride-induced 1,2-elimination of 2-(trimethylsilyl)aryl triflates. Consequently, arynes have been employed for the construction of multisubstituted arenes with structural diversity and complexity. The versatile transition-metal-free applications of arynes include cycloaddition reactions, insertion reactions and multicomponent reactions. In addition, arynes have found applications in natural product synthesis. Herein, we present a concise account of the major developments that occurred in this field during the past eight years.

Recent advances in transition-metal-free carbon–carbon and carbon–heteroatom bond-forming reactions using arynes

About two decades after Kobayashi's discovery in 1983 of a very mild way of generating highly reactive aryne intermediates, the synthetic community embraced o-(trimethylsilyl)aryl triflates as convenient and versatile aryne precursors for the synthesis of carbocycles and heterocycles, as well as natural products and pharmaceutically promising drug candidates. This review provides a comprehensive overview of the construction of heterocycles using Kobayashi's silylaryl triflate aryne precursors. It is organized according to the type of heterocycle generated.

Use of benzynes for the synthesis of heterocycles

Recent applications of aryne chemistry to organic synthesis. a review

A palladium-catalyzed domino aminopalladation/C-H functionalization sequence has been developed, and provides access to functionalized phenanthridines and isoquinolines. The use of butyronitrile as the solvent is determinant to the success of the domino process. [on SciFinder (R)]

Palladium-catalyzed annulation of acyloximes with arynes (or alkynes): synthesis of phenanthridines and isoquinolines

Adding an aryne to a tertiary allylamine affords o-allylaniline products of an aza-Claisen rearrangement. The aryne simultaneously provides the pi component for the rearrangement and the quaternization event that lowers the activation energy for the sigmatropic shift. The reaction was applied to the synthesis of medium-ring benzannulated amines (see scheme).

The Benzyne Aza‐Claisen Reaction

A new three-component coupling reaction of benzyne is described that uses two intermolecular carbopalladation reactions to produce 1,2-functionalized benzene derivatives.

Three-Component Coupling of Benzyne: Domino Intermolecular Carbopalladation

Biaryl synthesis via palladium-catalyzed aryne multicomponent coupling.

https://pubs.rsc.org/en/content/articlepdf/2013/cc/c3cc44529a

Tandem thia-Fries rearrangement – cyclisation of 2-(trimethylsilyl)phenyl trifluoromethanesulfonate benzyne precursors

https://onlinelibrary.wiley.com/doi/pdf/10.1002/anie.201206624

Jaclyn L. Henderson

Papers

The Benzyne Aza‐Claisen Reaction

Three-Component Coupling of Benzyne: Domino Intermolecular Carbopalladation

Biaryl synthesis via palladium-catalyzed aryne multicomponent coupling.

Tandem thia-Fries rearrangement – cyclisation of 2-(trimethylsilyl)phenyl trifluoromethanesulfonate benzyne precursors

Corrigendum: The Benzyne Aza-Claisen Reaction