# Ligand-Enabled Photocatalytic Reactivity of Iron(III) Halide Salts with Cyan and Green Light

## TL;DR

This paper shows how iron(III) salts can be used with visible light, including green light, to perform chemical reactions that typically require UV light.

## Contribution

The study introduces a new method to use longer wavelength visible light with iron(III) salts for photocatalytic C–H functionalizations.

## Key findings

- Iron(III) salts enable C–H functionalizations using visible light up to 525 nm.
- Aldehydes can be converted to amides, esters, and ketones using blue, cyan, and green light.
- The method allows for direct alkylation under visible light conditions.

## Abstract

Iron­(III) halide salts have emerged as cheap and efficient
catalysts
for photocatalytic transformations, including C–H alkylation,
C–H and alkene oxidation, azidation/amination, and others.
The majority of these methods require UV light (λ ≤ 390
nm), and systematic efforts to enable the use of lower-energy visible
light remain valuable. We report the use of simple Fe­(III) salts that
enable C–H functionalizations with longer wavelength visible
light up to 525 nm (green light). The one-pot conversion of aldehydes
to amides, esters, and ketones as well as direct alkylation are described
using blue, cyan, and green light.