Metal-Free Chlorodeboronation of Organotrifluoroborates

Abstract

A mild and metal-free method for the chlorodeboronation of organotrifluoroborates using trichloroisocyanuric acid (TCICA) was developed. Aryl-, heteroaryl-, alkenyl-, alkynyl- and alkyltrifluoroborates were converted into the corresponding chlorinated products in good yields. This method proved to be tolerant of a broad range of functional groups.

Transition Metal‐Free ipso‐Functionalization of Arylboronic Acids and Derivatives

“…[54] Several chlorination conditions were competent for the transformation of electron-rich aryltrifluoroborates to the corresponding chloroarenes. For example, in the presence of NaOCl or NaCl/chloramine-T, an assortment of chloroarenes was conveniently prepared from precursors bearing electron-donating groups.…”

Nitrosation of Aryl and Heteroaryltrifluoroborates with Nitrosonium Tetrafluoroborate

“…Recently, our group published the chlorodeboronation of aryl and heteroaryltrifluoroborates, which most likely occurs by an ipso- substitution (Scheme 2). 23 …”

α-Heteroarylation of Ketones <i>via</i> the Umpolung Reaction of <i>N</i>-Alkoxyenamine

“…Several reports have been published in the literature concerning the reaction of aryl borates with electrophiles, where the reaction does not proceed in a regioselective manner at the ipso-position. [20][21][22][23][24][25][26] Mayr and colleagues 27) reported that the presence of a trifluoroborate group at the 2-position of the indole effectively enhanced the nucleophilicity of the carbon at the 3-position, and demonstrated that the vicinal-activation of the indole with a trifluoroborate group was much more effective than ipso-activation. In the case of the indolylaluminum reagent, the presence of aluminum at the 2-position of N-methylindole may have enhanced the nucleophilicity of its 3-position, causing the reaction to occur preferentially at the 3-position of the indole.…”