Transition‐Metal‐Catalyzed Alkyne Hydroarylation with Arylmetals and Aryl Halides

Abstract

The aryl alkene is one of the most ubiquitous molecular scaffolds found in diverse natural products, materials, and pharmaceuticals. Aryl alkenes are also essential synthetic intermediates in both industrial and academic laboratories. Nevertheless, traditional preparative methods have fundamental disadvantages, such as the necessity of lengthy synthetic operations and difficulty in the site‐ and stereoselective construction of multiply substituted derivatives. The development of a more straightforward and site‐ and stereoselective method to prepare aryl alkenes has therefore been an important objective in organic chemistry. A particularly attractive method to synthesize aryl alkenes is transition‐metal‐catalyzed alkyne hydroarylation using aryl donor reagents, which proceeds through the formal addition of Ar–H across the carbon–carbon triple bond of an alkyne. This chapter provides an overview of alkyne hydroarylations catalyzed by homogeneous metal catalysts. The mechanism, selectivity, scope and limitations, and experimental conditions of transition‐metal‐catalyzed alkyne hydroarylations are surveyed according to the aryl donor reagent and its role in the reaction; namely, (1) alkyne hydroarylations using arylmetal reagents (alkyne carbometallation/protonation), and (2) alkyne hydroarylations using aryl halides (reductive Heck reaction).

Transition-Metal-Catalyzed Functionalization of Alkynes with Organoboron Reagents: New Trends, Mechanistic Insights, and Applications

“…This continued interest has resulted in the development of many efficient approaches showing great potential for sequential inter- and intramolecular C–C bond formation in a tandem, cascade, or one-pot fashion. Several excellent reviews have already partially covered this chemistry, some of them with a substantial focus on transition-metal-catalyzed alkyne hydroarylation with organoboron reagents, , including its application to the synthesis of heterocycles . However, to the best of our knowledge, there is no previous review on transition-metal-catalyzed functionalization of alkynes with organoboron reagents, even though major advances in the past decade have substantially broadened the scope of this field on several fronts.…”