Inside Back Cover: Site‐Selective Functionalization of Carboranes at the Electron‐Rich Boron Vertex: Photocatalytic B−C Coupling via a Carboranyl Cage Radical (Angew. Chem. Int. Ed. 37/2022)

Abstract

The site-selective functionalization … … of carboranes with multiple B À H sites is a long-standing challenge. In their Research Article (e202205672), Deshuang Tu, Changsheng Lu, Hong co-workers developed an efficient reaction protocol for the selective alkylation, alkenylation, and heteroarylation of carboranes under mild conditions via boron-vertex-centered carboranyl radicals generated by photo-induced decarboxylation of boron-substituted carborane carboxylic acids.

Visible-light-induced decarboxylation/defluorosilylation protocol for synthesis ofgem-difluoroalkenes

“…As we all know, gem -difluorovinyl groups, an important class of fluoroalkene structural motifs in medicinal and agrochemistry, exhibit steric and electronic profiles similar to those of the corresponding carbonyl substituents and accordingly have been widely used as ideal carbonyl isosteres in drug design. 12 Among them, an α-silylated gem -difluoroalkene, namely, gem -difluoroallylsilane, has recently drawn increasing attention because of the value of the gem -difluoroalkene itself and the importance of organosilicon compounds. 13,14 gem -Difluoroallylsilane compounds are typically synthesized via the following methods: (1) an S N 2′-type reaction of pre-synthesized Si–Li/Mg reagents with fluoroalkenes; 15 (2) an alkoxy base mediated defluorosilylation of trifluoromethyl alkenes with silylboronates via a strong nucleophilic silyl anion complex; 16 (3) a copper-catalyzed defluorosilylation of trifluoromethyl alkenes with silylboronates in the presence of specific ligands.…”

Recent Advance in Transition Metal‐Catalyzed Carboxylic Acid Guided B−H Functionalization of Carboranes

“…Very recently, a photocatalytic B−C coupling for the selective functionalization of carboranes with organofluorine compounds was reported by Yan's group (Scheme 18). [30] The radical trapping experiment demonstrated the generation of a boron vertex‐centered carboranyl radical under photo‐induced conditions and this carboranyl radicals played a key role in this reaction through a single‐electron transfer during decarboxylation. This represents a novel strategy which alkyl, alkenyl and heteroaryl groups were selectively installed into the boron site under mild conditions, leading to a series of fluorinated carborane derivatives.…”

One‐Dimensional Covalent Organic Frameworks for the 2e− Oxygen Reduction Reaction

“…For example, Jiang and co-workers constructed 3D COFs for the CO 2 RR that displayed considerably higher activity and selectivity towards the CO 2 RR than did 2D COFs. [11] Compared to 2D COF planes, 1D COFs have more edge sites and a lower density of basal sites. This facilitates mass transport to the active sites of the framework and improves the catalytic efficiency (Figure 1A).…”