Catalyst‐free Synthesis of Benzothiazolopyrimidines via Visible‐Light‐Induced Wolff Rearrangement/[4+2] Cycloaddition Process

Abstract A visible‐light‐induced highly practical catalyst‐free Wolff rearrangement/domino [4+2] cycloaddition of 2‐benzothiazolimines with α‐diazo ketones has been developed. This protocol provides a concise and facile synthetic approach to construct a broad range of benzothiazolopyrimidine derivatives bearing a quaternary carbon center under mild reaction conditions with high isolated yields and excellent diastereoselectivities (up to >99% yield and >20 : 1 d.r.).