Cytosine Palladium Hybrid Complex Immobilized on SBA-15 as Efficient Heterogeneous Catalyst for the Aqueous Suzuki-Miyaura Coupling

The synthesis of new heterogeneous catalysts has been achieved by the coupling of palladium on cytosine functionalized SBA-15 nanoreactors (Pd-Cyt@SBA-15). The nanocatalytic systems show a surface area of 367 m2 g-1 with a mean pore diameter of 3.45 nm. Low angle-XRD measurement reveals that the the anchoring of Pd inside the mesoporous channels of cytosine functionalized SBA-15 (Cyt@SBA-15) does not seriously disturb the overall ordered structure of the mesoporous silica. The hybrid nanoreactors act as highly active catalysts for the Suzuki-Miyaura cross-coupling of a variety aryl chlorides and boronic acid in mixtures of isopropyl alcohol/water under mild conditions. The catalysts showed excellent reusability over seven successive runs under the given reaction conditions. Likewise, no significant leaching of the palladium was detected in the nanoreactors after reusing them several times. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim