Pinacolborane coupling with aryl halides

Suzuki and Stille couplings. For coupling of aryl chlorides with arylboronic acids the catalytic system contains (CyjPjjPdClj, CsF in NMP. co-Arylalkanoic acids are prepared by coupling of aryl halides with carboxylic esters bearing a 9-BBN substituent at the other terminus, and saponification. A biaryl synthesis from two different aryl halides is accomplished with in situ boronate formation which depends on the (dppfjPdClj catalyst. For access to aryl boronates either the coupling of aryl triflates with bis(pinacolato)diboron" or that of aryl iodides with pinacolborane may be employed. 

Recently, a novel coupling reaction, based on the used of pinacolborane as an efficient reagent for the electrochemical functionalization of aryl halides in the presence of an Mg anode afforded arylboronic pinacol esters [2]. However, this reaction presents some limitations low faradic efficiencies with aryl chlorides,... 

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