Hydrometallation of Conjugated 1,3‐Diynes

Abstract

Hydrometallation reactions are a powerful tool in the synthesis of saturated and unsaturated organometallic compounds, which are commonly used as synthons in organic chemistry and components of new materials. The addition of the HE bond to different unsaturated compounds possessing the CC triple and double bonds, as well as CO, CN, has been broadly described in many reviews in recent decades. More challenging compounds like, for instance, conjugated 1,3‐diynes, which furnish enynes, dienes, allenes, polymers, or cyclic products in the hydrometallation reactions have recently started to attract attention as important building blocks in the synthesis of fine chemicals . The possibility of obtaining a specific molecule with strictly defined regio‐ and stereoselectivity is highly attractive for various branches of chemistry, but on the other hand, it is a demanding synthetic task. Within this article, we would like to introduce readers to the subject of hydrometallation of conjugated 1,3‐diynes, which generates various products depending on the reaction conditions, the type of catalyst, and the electronic and steric properties of reagents. This article is divided according to the type of hydrometallation reaction (hydromagnesation, hydroboration, hydroalumination, hydrosilylation, hydrogermylation, hydrostannation, and hydrotelluration) as well as the type of product formed (enynes, dienes, cyclic compounds, and polymers) and process regio‐ and stereoselectivity. The idea is to provide a guidebook, which will be helpful in the preparation of a specific product depending on the hydrometallation reaction and process conditions.