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A closed system has been designed to perform microdroplet/thin film reactions with solvent recycling capabilities for gram-scale chemical synthesis. Claisen–Schmidt, Schiff base, Katritzky and Suzuki coupling reactions show acceleration factors relative to bulk of 15 to 7700 times in this droplet spray system. These values are much larger than those reported previously for the same reactions in microdroplet/thin film reaction systems. The solvent recycling mode of the new system significantly improves the reaction yield, especially for reactions with smaller reaction acceleration factors. The microdroplet/thin film reaction yield improved on recycling from 33% to 86% and from 32% to 72% for the Katritzky and Suzuki coupling reactions, respectively. The Claisen–Schmidt reaction was chosen to test the capability of this system in gram scale syntheses and rates of 3.18 g per h and an isolated yield of 87% were achieved.
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This content will become publicly available on December 1, 2026
Liquid Crystal‐Driven Chemical Feeding Accelerates Condensation Reactions in Droplet Microreactors
Abstract Droplet microreactors have gained significant attention as confined spaces for chemical reactions, offering enhanced reaction rates and control. However, the impact of mass transfer induced by chemical feeding within these microreactors remains largely unexplored. In this study, a novel approach is demonstrated using liquid crystal (LC) phase transitions to feed chemicals from a bulk LC film to droplet microreactors situated on the LC film. By manipulating LC mesophases, precise control is achieved over the solubility of chemicals within the bulk LC, enabling both in situ loading and controlled release. The results reveal that while droplet confinement inherently enhances reaction rates, the chemical feeding further improves mass transport within the droplet microreactors. This synergistic effect leads to a remarkable acceleration of chemical reactions, with conversion rates up to nine times higher than conventional bulk reactions. Furthermore, the broad applicability of this approach is demonstrated across various aldehyde reactions, the reusability of the LC films for multiple reaction cycles, and multi‐step microscale synthesis within a single droplet microreactor. These findings establish the LC system as an innovative platform for chemical feeding, substantially expanding the performance and utility of droplet microreactors for diverse chemical applications.
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- Award ID(s):
- 2227991
- PAR ID:
- 10681821
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Advanced Science
- Volume:
- 12
- Issue:
- 45
- ISSN:
- 2198-3844
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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