Publication – Greening heterogeneous catalysis for fine chemicals

Tetrahedron Letters, 54 (2013) 1129–1132.

Valerica Pandarus^(a), Rosaria Ciriminna^(b), François Béland^(a), Genevieve Gingras^(a), Maxime Drobot^(c), Omar Jina^(c), Mario Pagliaro^(b)
a) SiliCycle Inc., 2500, Parc-Technologique Blvd, Quebec City, Quebec, Canada G1P 4S6
b) Istituto per lo Studio dei Materiali Nanostrutturati, CNR, via U. La Malfa 153, 90146 Palermo, Italy
c) Syrris Ltd., 27 Jarman Way, Royston, Hertfordshire SG8 5HW, United Kingdom

This paper describes how flow chemistry can be successfully used to enhance heterogeneous catalytic reactions. A series of C-C Suzuki Miyaura coupling reactions using different aryl halide substrates are optimized on an Asia 220 system.

Following efficient mixing of the reagents, prior to reaction over Pd-catalyst, much faster and more selective reactions were achieved. The oxidation of benzyl alcohol in flow using metal free catalyst SiliaCat TEMPO was also explored. By using flow chemistry, a one-hour batch process was successfully achieved in under a minute with 100% conversion and selectivity.

Abstract: Simple flow chemistry technology coupled to newly developed solid organosilica catalysts can be successfully applied to enhance the efficiency and selectivity of two representative homogeneous syntheses widely employed by chemical companies. The method is general and can be extended to many other reactions using similar solid catalysts to afford reactions that are faster and cleaner than conventional homogeneous and heterogeneous conversions.

This paper uses an Asia flow chemistry system.