Polyborylated reagents for modern organic synthesis

Abstract

Diverse kinds of gem- and vic-diborylated compounds are now readily available thanks to advances in gem-diborylation of lithium carbenoids as well as vic-diborylation of carbon–carbon multiple bonds with diboron compounds. These diborylated reagents lead to invention of polyborylated reagents and many novel and useful synthetic methods for supreme stereocontrol. This review summarizes preparative methods and synthetic reactions of di- and polyborylated reagents with the emphasis on multiple bond formation.

Recent Advances in the Addition of Amide/Sulfonamide Bonds to Alkynes

“…The addition of atom–atom bonds to alkynes has become an important strategy for the functionalization of carbon–carbon triple bonds [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16]. These intermolecular and intramolecular addition reactions provide a facile and efficient access to highly functionalized alkenes and cyclic compounds, respectively, in a high atom- and step-economic manner.…”

Palladium‐Catalyzed Annulation of vic‐Bis(pinacolatoboryl)alkenes and ‐phenanthrenes with 2,2′‐Dibromobiaryls: Facile Synthesis of Functionalized Phenanthrenes and Dibenzo[g,p]chrysenes

“…[9] Various vic-diborylated alkenes have been converted into multisubstituted acyclic alkenes by stepwise cross-coupling reactions with two organic halides, [10] whereas the double cross-coupling reaction of vic-diborylated compounds with aromatic dihalides as a synthetic method for functionalized PAHs remains unexplored. [11][12][13] We report herein a palladium-catalyzed double cross-coupling reaction of vic-diborylated alkenes (1) and phenanthrenes (2) Initially, we chose (Z)-1,2-bis(pinacolatoboryl)stilbene (1 a) as a model vic-diborylalkene and 2,2'-dibromobiphenyl (3 a) as a coupling partner [Eq. (1)].…”

Direct Synthesis of Multi(boronate) Esters from Alkenes and Alkynes via Hydroboration and Boration Reactions

“…Despite their high synthetic value and wide range of potential applications, there is a limited number of efficient and atom-economical procedures available for the preparation of multi­(boronate) esters . Traditionally, they were synthesized from organic halides, which typically generate stoichiometric amounts of salts, require a large quantity of strong base, and have narrow substrate and poor functionaly tolerance.…”