Bromination of Thiophene in Micro Reactors

Title: Bromination of Thiophene in Micro Reactors

Volume: 2 Issue: 8

Author(s): Patrick Lob, Volker Hessel, Heinrich Klefenz, Holger Lowe and Kyra Mazanek

Affiliation:

Keywords: Chemical micro process engineering, Micro reactors, Brominations, Thiophene bromination

Abstract: A solvent-free continuous bromination reaction of thiophene in a micro reactor rig was developed, using pure bromine and aromatic without any catalyst at room temperature processing. This micro-reactor operation led to high selectivities for the bromination of 2,5-dibromo-thiophene (at about complete conversion) and yields up to 86%, which is better than for self-made batch processing (77% yield) and literature data (50% yield). In addition, the reaction time could be reduced from about 2 hours to less than 1 second. Correspondingly, the space-time yields were higher by order of magnitude for the continuous microreactor process as compared to batch operation. The micro reactor allowed a fast parametric study and in this way to reliably find optimal operating conditions with regard to temperature and the bromine-to-thiophene molar ratio. The study was complemented by a comparison of two different micro mixers, a T-junction with minute internals, and batch processing under optimal conditions.

Cite this article as:

Lob Patrick, Hessel Volker, Klefenz Heinrich, Lowe Holger and Mazanek Kyra, Bromination of Thiophene in Micro Reactors, Letters in Organic Chemistry 2005; 2 (8) . https://dx.doi.org/10.2174/157017805774717517