Unveiling Latent Photoreactivity of Imines

Abstract

Unlike carbonyl compounds, it has long been common understanding that excited imines show virtually no photoreactivity, and hence their properties and potential utility in chemical science remain largely unexplored. Now, a strategy is presented for eliciting latent photoreactivity of imines based on the introduction of a donor–acceptor (D‐A) structure to extend the lifetime of their photoexcited states. A series of spectroscopic analyses and density functional theory calculations reveal unique photophysical properties of the D‐A‐type imines. Furthermore, the reactivity of the D‐A‐type imines is demonstrated by using them as a photoredox catalyst for atom‐transfer radical addition. These findings illuminate a previously neglected chemical space in the field of photochemistry, which will be exploited by taking advantage of the inherent structural modularity of imines.

Beyond Traditional Synthesis: Electrochemical Approaches to Amine Oxidation for Nitriles and Imines

“…[5][6][7][8]72 Nitriles can also be obtained from primary amines, while the oxidation of secondary amines can yield imines as a product (Scheme 2). 9,10 The first nitrile compound, benzonitrile, was synthesized in 1832 by Wohler and Liebigg; afterward, in 1834, Pelouze successfully prepared acetonitrile. 2 In the 1930s, nitrile was synthesized through cyanide, aryl halides, and organometallic compounds.…”

“…Nitriles can also be obtained from primary amines, while the oxidation of secondary amines can yield imines as a product (Scheme ). , …”

Photochemical radical cyclization reactions with imines, hydrazones, oximes and related compounds

“…14 In this regard, they may be compared to corresponding carbonyl compounds. 15 One of the privileged photochemical processes is the fragmentation of the N-N or the N-O bond. Thus a variety of N-centered radicals are generated.…”