Photoinduced Etherification of Less-Strained Cycloketoxime Esters Enabled by C–C Bond Cleavage

Abstract

We report a general, scalable, and convenient photochemical process for diversities of distal oxygenated nitriles from corresponding less-strained ketoxime esters allowing one-step introductions of ether and cyano groups, which avoids the utilization of toxic cyanide reagents. A wide range of ketoxime esters involving five-membered to eight-membered cycloketoxime esters and linear ketoxime esters participate smoothly under operately simple and mild conditions, affording structurally variable ring-opening products.

Branching out: redox strategies towards the synthesis of acyclic α-tertiary ethers

“…Recently, Zhao reported the photoinduced etherification of cycloketoxime esters. 376 It was proposed that the photoexcited Ir( iii ) photocatalyst was quenched via SET by the cycloketoxime substrate to give an imine radical, which subsequently rearranged via C–C bond cleavage to give a distal radical (Scheme 100). This radical could be further oxidised by the photocatalyst to give the corresponding cation, which was intercepted by an alcohol to yield the ether product.…”

Photoinduced Remote C(sp3)–H Cyanation and Oxidation Enabled by a Vinyl Radical-Mediated 1,5-HAT Strategy

“…Prompted by the results described above, we next evaluated other types of nucleophiles available in this photoinduced remote functionalization. , As shown in Scheme , it is worth mentioning that the γ-position of the alkene moiety upon visible-light irradiation could be functionalized with alcohol nucleophiles. It was found that methanol and ethanol were capable of serving as suitable nucleophiles, giving rise to products 5a and 5b , respectively, in moderate yields with >20/1 stereoselectivity.…”