Electrochemical Synthesis of Potassium Aryltrifluoroborates

Abstract

Potassium aryltrifluoroborates were efficiently synthesized using an electrochemical method for the reduction of the corresponding aryl bromides in the presence of triisopropyl borate. The products were obtained in short reaction times with moderate to good yields at room temperature. The methodology is simple, fast and efficient, and is synthetically useful once it was applied in the synthesis of a fragment of combretastatin D2, a natural product with antiproliferative activity.

Electrochemical synthesis and transformation of organoboron compounds

“…7 In 2014, Menezes and Navarro reported the synthesis of potassium aryltrifluoroborates via the electrochemical borylation of aryl bromides with triisopropyl borates and subsequent in situ treatment with potassium hydrogen difluoride (Scheme 2c). 8 Generally, these transformations proceeded via similar mechanisms. Organic halides were reduced at the cathode to form carbanions, which further reacted with boron electrophiles to produce organoboron compounds.…”

Electroreduction strategy: a sustainable tool for the generation of aryl radicals

“…Based on these finding, Menezes et al utilized a well-established electroreductive borylation strategy to complete the construction of potassium aryltrifluoroborates in a one-pot two-step process in moderate yields (Scheme 8). 32…”

Progress in the Electrochemical Synthesis of Organoboron Compounds

“…Paulo H. Menezes et al developed an efficient method for synthesizing potassium aryltrifluoroborates using electrochemical reduction of aryl bromides in the presence of triisopropyl borate (Scheme 8). [67] This method was quick, easy, and tolerate to a variety of functional groups in the starting material (aryl bromide) and the electronic properties of the substituents have little effect on the yield of the reaction, as those containing acidic functions. Overall, this suggests that the method is versatile and can be applied to a wide range of starting materials produced moderate-to-good yields of the intended products.…”