Hypervalent iodine-mediated β-difluoroalkylboron synthesis an unusual 1,2-hydrogen shift enabled by boron substitution.

β-Difluoroalkylborons, featuring functionally important CF moiety and synthetically valuable boron group, have great synthetic potential while remaining synthetically challenging. Herein we report a hypervalent iodine-mediated oxidative -difluorination strategy to realize the construction of -difluorinated alkylborons an unusual 1,2-hydrogen migration event, in which the (-methyliminodiacetyl) boronate (BMIDA) motif is responsible for the high regio- and chemoselectivity. The protocol provides facile access to a broad range of β-difluoroalkylborons under rather mild conditions.

Diversity-Oriented Synthesis of α-Functionalized Acylborons and Borylated Heteroarenes by Nucleophilic Ring Opening of α-Chloroepoxyboronates.

The ring-opening reactions of N-methyliminodiacetyl (MIDA) α-chloroepoxyboronates with different nucleophiles allow the modular synthesis of a diverse array of organoboronates. These include seven types of α-functionalized acylboronates and seven types of borylated heteroarenes, some of which are difficult-to-access products using alternative methods. The common synthons, α-chloroepoxyboronates, could be viably synthesized by a two-step procedure from the corresponding alkenyl MIDA boronates.

Regio- and Diastereoselective Synthesis of Cyclohexadienylborons via an Intermolecular Diels-Alder Reaction of Alkenyl MIDA Boronates with 2-Pyrones.

An efficient synthesis of highly functionalized cyclohexadienylborons via an inverse electron-demand Diels-Alder reaction/CO extrusion of alkenyl MIDA boronates with 2-pyrones is outlined. By controlling the reaction temperature, the corresponding C(sp )-rich bicyclolactones could also be readily formed. The exo-selective reactions feature good functional-group tolerance, broad substrate scope, and excellent regio- and diastereoselectivity.

gem-Difluorination of Alkenyl N-methyliminodiacetyl Boronates: Synthesis of α- and β-Difluorinated Alkylborons.

Organofluorine compounds are widely used in pharmaceutical, agrochemical, and materials sciences. The syntheses and applications of fluorinated organoborons facilitate the rapid and modular assemblies of fluorine-containing molecules because of the versatility of C-B bonds in diverse chemical transformations. Reported herein is a migratory geminal difluorination of aryl-substituted alkenyl N-methyliminodiacetyl (MIDA) boronates using commercially available Py⋅HF as the fluorine source and hyperiodine as the oxidant.