Harnessing Cooperative Energy Transfer and Hydrogen Atom Transfer for Direct Nitrogenations of Non‐Activated Alkanes

TL;DR

This paper introduces a new metal-free method for directly converting alkanes into amines using a unique combination of energy and hydrogen atom transfer.

Contribution

A novel strategy for direct nitrogenation of non-activated alkanes using a photocatalytic system and in situ nitrene radical generation.

Findings

The method enables direct C─N bond formation from unactivated alkanes under mild conditions.

The reaction mechanism involves cooperative energy transfer and hydrogen atom transfer.

The process is scalable and sustainable, producing a variety of cycloalkylamines.

Abstract

While important progress has been achieved recently on direct functionalization of alkanes via photocatalytic methods, direct amination of aliphatic compounds remains a great challenge. Herein we report a conceptually new strategy towards direct conversion of hydrocarbons into amines, based on in situ generation of nitrene radical. Energy transfer between thioxanthone (TXO) photocatalyst and iminoiodinane furnishes the triplet nitrene radical, able to undergo HAT reaction promoting alkane activation and subsequent C─N bond formation step. The user‐friendly nature of the metal‐free transformation, along with mild reaction conditions further highlight the sustainability of this scalable process delivering a diversity of cycloalkylamines. Combined experimental and computational mechanistic studies support the unusual reaction mechanism.

Cooperative EnT & HAT: New solution for direct C─N coupling of unactivated alkanes. Metal‐free photocatalytic nitrogenation. Use of unactivated alkanes. Original reaction pathway.

Figures