Abstract
As renewable lignin building blocks, hydroxystyrenes are particularly appealing as either a replacement or addition to styrene-based polymer chemistry. These monomers are obtained by decarboxylation of phenolic acids and often subjected to chemical modifications of their phenolic hydroxy groups to improve polymerization behaviour. Despite efforts, a simple, scalable, and purely (chemo)catalytic synthesis of acetylated hydroxystyrenes remains elusive. We thus propose a custom-made chemoenzymatic route that utilizes a phenolic acid decarboxylase (PAD). Our process development strategy encompasses a computational solvent assessment informing about solubilities and viable reactor operation modes, experimental solvent screening, cascade engineering, heterogenization of biocatalyst, tailoring of acetylation conditions, and reaction upscale in a rotating bed reactor. By this means, we established a clean one-pot two-step process that uses the renewable solvent CPME, bio-based phenolic acid educts and reusable immobilised PAD. The overall chemoenzymatic reaction cascade was demonstrated on a 1 L scale to yield 18.3 g 4-acetoxy-3-methoxystyrene in 96% isolated yield.
| Original language | English |
|---|---|
| Journal | Green Chemistry |
| Volume | 24 |
| Issue | 18 |
| Pages (from-to) | 6889-6899 |
| Number of pages | 11 |
| ISSN | 1463-9262 |
| DOIs | |
| Publication status | Published - 8 Aug 2022 |
Keywords
- CATECHOL
- CHEMISTRY
- CINNAMIC-ACIDS
- DECARBOXYLATION
- LIQUID-LIQUID EQUILIBRIA
- PLUS WATER
- POLYMERIZATION
- POLYMERS
- SOLUBILITY
- SOLVENTS