Cascade Photofragmentation/Photoalkylation for the Synthesis of α-Tertiary Alkyl Primary Amines

<i>N</i>-H imines are synthetically versatile but sensitive intermediates in organic synthesis. This work introduces a cascade synthesis of basic amines through <i>N</i>-H imine intermediates, featuring an efficient <i>aza</i>-Norrish Type II fragmentation, followed by photoalkylation. Our method selectively converts bench-stable phenacylamines to α-quaternary primary amines in one pot using mild and metal-free UV photocatalysis. Our work constitutes a rare use of amine photofragmentation in organic synthesis.