Pd/Cu-catalyzed oxidation of alkynes into 1,2-diketones using DMSO as the oxidant
摘要:
A facile and practical method for the palladium/copper-catalyzed transformation of internal alkynes into 1,2-diketones has been described, affording the desired products in moderate to excellent yields. The mechanistic studies were also preliminarily pursued using diphenyl sulfoxide as the oxidant, and the diphenyl sulfide was isolated as the reduced product. (C) 2012 Elsevier Ltd. All rights reserved.
Carbon carbon bond forming reactions: Application of covalently anchored 2,4,6-triallyloxy-1,3,5-triazine (TAT) Pd(II) complex over modified surface of SBA-15 to Heck, Suzuki, Sonogashira and Hiyama cross coupling reactions
摘要:
A highly active SBA-15-TAT-Pd(II) catalyst was synthesized from organofunctionalized SBA-15 and 2,4,6-triallyloxy-1,3,5-triazine. The catalyst was employed in carrying out Heck, "copper-free" Sonogashira, Suzuki and Hiyama cross coupling reactions. Under the optimized conditions the catalyst displays excellent catalytic activity in delivering the desired products in good to excellent yields. The catalytic system exhibited superior activity regarding the time taken for the completion of reaction, isolation, Pd loading (0.62 mmol%) and yields of products as compared to the earlier reported heterogeneous SBA-15 anchored Pd catalysts. The catalyst could be recycled and reused for five times without any appreciable loss of catalytic activity. (C) 2015 Elsevier B.V. All rights reserved.