Synthesis of γ-amino acids via photoinduced hydrocarboxylation of allylamines

Herein, we disclose a new photochemical process to prepare γ-amino acids from allylamines and formic acid salts. The investigated redox-neutral hydrocarboxylation process produces high yields across a wide range of functionalized allylamine substrates with excellent regioselectivity. The developed operationally simple protocol can be readily scaled with low photocatalyst loading (from 1% up to 0.02 mol%) without the need for any precautions to exclude air or moisture. The mechanistic working model utilizes a thiol-catalyzed radical chain process, delivering the hydrogen atom and CO2 from formate across the alkene substrate through the carboxylate radical (CO2•-), a crucial reactive intermediate