Overview of Regioselective and Stereoselective Catalytic Hydroboration of Alkynes

Abstract

Hydroboration of alkynes is of special interest to researchers since it is the most straightforward process for the synthesis of highly important vinylborane synthetic intermediate compounds. It is significant in terms of both regioselectivity and stereoselectivity, since several positional isomers are formed during the process of hydroboration. Given the importance of this class of compounds, an extensive study has been carried out regarding catalytic condition development and detailed mechanistic studies for selectively obtaining a single isomer. This review comprehensively summarizes both the regioselective and stereoselective catalytic hydroboration of alkynes. It is aimed at giving readers accurate knowledge of the catalytic systems available for the hydroboration of certain alkynes. We anticipate that this inclusive review will encourage researchers to explore more new types of catalytic systems to achieve the remarkable process of hydroboration of alkynes.

Integrating Terminal CoBrn Salts into a 2D Cobalt(II) Coordination Polymer to Promote the β‐(E)−Selective Hydroboration of Alkynes

“…Therefore, the chemo‐, regio‐, and stereoselective hydroboration of alkynes under homogeneous conditions by using H‐[B] as boron reagent have been well explored (Scheme 1). [12] Earth‐abundant cobalt salts are among the most promising base metals in hydroboration catalysis of alkynes [5a,6a,13] . However, limited studies have focused on the hydroboration of alkynes with well‐defined cobalt‐based catalysts to obtain vinyl boronates.…”

Catalytic Hydrofunctionalization Reactions of 1,3-Diynes

“…Organoboron compounds are important building blocks in organic chemistry because of their low toxicity, stability, and unique reactivity in various synthetic processes, as, for example, in the well-known Suzuki-Miyaura-type cross-couplings or the Petasis borono-Mannich reactions. In this context, the hydroboration of alkynes, including both metal-free and transition-metal-catalyzed reactions, has been widely studied in the last decades, as it provides a simple and straightforward access to valuable vinylborane synthetic intermediate compounds [16]. However, as a special class of alkynes, 1,3-diynes have been barely investigated in hydroboration processes.…”

Aluminium complexes: next-generation catalysts for selective hydroboration

“…Amongst various methods used to synthetically prepare useful organoboranes, one of the most fundamental methods is the hydroboration of any unsaturated C–X bonds. 1–12 The first example of hydroboration is the pioneering work by Brown et al where a H–B bond was added to an alkene in an anti -Markovnikov fashion (Scheme 1a). 13–15 The most straightforward hydroboration reagent involves the use of diborane ((BH 3 ) 2 ) or an adduct formed with THF (BH 3 ·THF) or alkyl borane (Scheme 1b).…”