Air stable ligandless heterogeneous catalyst systems based on Pd and Au supported in SiO(2) and MCM-41 for Suzuki-Miyaura cross-coupling in aqueous medium

• Published in: Applied catalysis. A, General Vol. 462-463; pp. 39 - 45
• Main Authors: Speziali, Marcelo Gomes, Da Silva, Anderson Gabriel Marques, De Miranda, Debora Michelini Vaz, Monteiro, Adriano Lisboa, Robles-Dutenhefner, Patricia Alejandra
• Format: Journal Article
• Language: English
• Published: 10.07.2013
• Subjects: Catalysis; Catalysts; Catalytic activity; Chemisorption; Gold; Palladium; Silicon dioxide; Sol gel process
• ISSN: 0926-860X

Palladium and palladium-gold containing siliceous-MCM-41 and sol-gel palladium and palladium-gold silica composites have been prepared. The catalytic performance of incorporated Pd/MCM-41, Au-Pd/MCM-41 and Pd and Au-Pd/SiO(2) sol-gel catalysts for the Suzuki-Miyaura cross-coupling reaction was determined and the influence of the matrix and the catalyst composition on the catalytic activity were also studied. The catalysts were characterized by N(2) physisorption (BET/BJH methods). X-ray diffraction, temperature programmed reduction analysis, H(2) chemisorption, atomic absorption spectrophotometry and Raman spectroscopy. The silica-containing palladium and palladium-gold catalysts prepared using the MCM-41 matrix showed greater catalytic activity than using the conventional sol-gel method; however, gold had a significant influence on this reaction. The catalyst did not undergo metal leaching and could be easily recovered and re-used (reused).