# Selective Transfer Hydrogenation of Furfural to Isopropyl Levulinate: An In Situ One‐Pot Cascade Approach

## TL;DR

This paper describes a method to convert furfural into isopropyl levulinate using a catalyst system that suppresses unwanted byproducts.

## Contribution

A novel Ru-based catalyst system is introduced for selective conversion of furfural into isopropyl levulinate with high yield.

## Key findings

- Isopropyl levulinate was obtained with 67% yield using Ru-MACHO-BH catalyst.
- The catalyst system suppressed humin and high molecular weight byproducts.
- The cascade reaction can be directed to produce γ-valerolactone with 15% yield.

## Abstract

Within the current article, we were interested in describing the complete conversion of furfural (FF) as a green starting material to small oxygenates using isopropanol (IPA) as a solvent and as a H‐donor. We applied a series of Ru‐based complexes, and found that the most active Ru‐complex in terms of isopropyl levulinate (IPL) formation at 130°C after 21 h was Ru‐MACHO‐BH (Ru‐MACHO‐BH = carbonylhydrido[2‐(diphenylphosphino‐κP)‐N‐[2‐(diphenylphosphino‐κP)ethyl]ethanamine‐κN][tetrahydridoborato(1‐)‐κH]ruthenium(II)). We used two catalytic functions, one was the metal function to cover the hydrogenation of the aldehyde by Ru, and a Brønsted acidic function to secure the specific sub‐steps of the reaction network (e.g.: hydrolysis of furfuryl alcohol as an intermediate, hydrolysis of 2‐(isopropoxymethyl)furan (FE) to IPL). We observed that, the harmonization of these two functions leads to a highly selective reaction toward IPL (complete conversion, 67% yield). Furthermore, the reaction cascade can be directed until the final product, γ‐valerolactone (GVL) (15% yield). The Brønsted acid−Ru‐MACHO‐BH catalyst system provides a unique reaction media where the usual humin/high molecular weight side products formation can be suppressed, while the nature of catalysis stays intact (homogeneous during the entire reaction coordinate).

In this article, we applied a combination of metal (0.5 mol%) and acid (1 mol%) that functioned harmoniously to selectively convert a bio‐based starting material, furfural, into small oxygenates. We used a transfer hydrogenation reaction with isopropanol acting as both the reducing agent and the reaction medium. Isopropyl levulinate, a key intermediate in the chemical industry, was isolated as the major product with a yield of 67%.© 2026 WILEY‐VCH GmbH