Aminomethylation of Aryl Halides Using α-Silylamines Enabled by Ni/Photoredox Dual Catalysis

Abstract

A protocol for the aminomethylation of aryl halides using α-silylamines via Ni/photoredox dual catalysis is described. The low oxidation potential of these silylated species enables facile single electron transfer (SET) oxidation of the amine followed by rapid desilylation. The resulting α-amino radicals can be directly funneled into a nickel-mediated cross-coupling cycle with aryl halides. The process accomplishes aminomethylation under remarkably mild conditions and tolerates numerous aryl- and heteroaryl halides with an array of functional groups.

Alkyl Carbon–Carbon Bond Formation by Nickel/Photoredox Cross‐Coupling

“…[10] Subsequently,m ultiple strategies for C(sp 3 )r adical generation have been developed. Some approaches rely on redox-active groups,s uch as alkyltrifluoroborates,c arboxylates,b is(catecholato)silicates, and 1,4-dihydropyridines,t oa chieve programmed reactivity ( Figure 3), and others utilize the innate reactivity of substrates (via hydrogen or halogen atom transfer) to generate alkyl radicals.R adicals originating from the oxidation of sulfinate salts, [21] xanthates, [22] and a-silylamines [23] have also been employed in this cross-coupling strategy,a lthough they are not discussed in this Minireview.…”

Photoredox Generation of Carbon‐Centered Radicals Enables the Construction of 1,1‐Difluoroalkene Carbonyl Mimics

“…These amines readily undergo desilylative fragmentation following single electron oxidation of the nitrogen’s lone pair. [14] Difluoroalkenes bearing cyclic and acyclic amines were isolated in good yields.…”

Synergisms Between Metal and Photoredox Catalysis: Deconvoluting Complex Systems

“…Coupling reactions involving C-X (X = heteroatom) have been also investigated by means of the merger of Ni catalysis with photoredox catalysis. The formation of C-N bonds has been reported by the groups of Jamison, 185 Oderinde and Johannes, 186 Buchwald and MacMillan 187 and Molander 188 (Scheme 14). The work of Jamison involves the conversion of iodoacetanilides 72 and alkenes 73 to indolines 74.…”