Overview

• The NGO membrane reactor converts key intermediates to propranolol with nearly 100% conversion and selectivity in just 4.63 seconds at 23 °C.
• Nanoscale confinement within amine-functionalized graphene oxide layers streamlines molecular interactions to suppress by-product formation.
• Mild thermal annealing fine-tunes membrane interlayer spacing to lower activation energy for desired reactions and raise barriers to unwanted side reactions.
• The continuous-flow system attains a turnover frequency of 17.48 h⁻¹, far exceeding the 2.27 h⁻¹ achieved by NGO powder catalysts under identical conditions.
• Demonstrated versatility includes high-efficiency synthesis of metoprolol, bisoprolol, pindolol and naftopidil, indicating broad scalability for beta-blocker manufacturing.