# Nickel‐Catalyzed Hydro‐ and Deutero‐dehalogenations of (Hetero)Aryl Halides under Aqueous Micellar Catalysis Conditions

## TL;DR

A new nickel-catalyzed method efficiently replaces halogens with hydrogen or deuterium in aromatic compounds under eco-friendly conditions.

## Contribution

A green nickel-catalyzed method enables efficient hydro- and deuterodehalogenation of aryl/heteroaryl halides in aqueous micellar conditions.

## Key findings

- Over 40 aryl/heteroaryl halides were successfully converted to (hetero)arenes with excellent yields.
- The process uses low nickel catalyst (2–6 mol %) and is conducted in recyclable aqueous media with low E-Factors.
- The method works with sterically hindered substrates and carbon-fluorine bonds in drug molecules.

## Abstract

Efficient Ni‐catalyzed hydrodehalogenations and deuterodehalogenations of aryl/heteroaryl halides are reported herein. This new technology can be used to incorporate not only hydrogen, but also deuterium into various aromatic/heteroaromatic compounds with high efficiency, using 2–6 mol % nickel in the presence of stoichiometric NaBH4. Over 40 examples have been successfully converted to the corresponding (hetero)arenes in excellent yields. The process is conducted under green chemistry conditions: in water enabled by designer surfactants, a medium which can be readily recycled. Minimal organic solvent, needed given the small (academic) scale of the reactions, is used for product isolation, resulting in low E‐Factors. Additionally, sterically hindered substrates are amenable, as are selected APIs that feature carbon‐fluorine bonds.

Efficient Ni‐catalyzed hydrodehalogenations and deuterodehalogenations of aryl/heteroaryl halides are reported. This new technology applies to highly functionalized drugs and drug intermediates. The overall greenness is demonstrated via recyclability of the aqueous reaction media and associated overall low E‐Factors.