Supported Anionic Gold Nanoparticle Catalysts Modified Using Highly Negatively Charged Multivacant Polyoxometalates
K. Xia, T. Yatabe, K. Yonesato, T. Yabe, S. Kikkawa, S. Yamazoe, A. Nakata, K. Yamaguchi, K. Suzuki
Angew. Chem. Int. Ed., Accepted.

Although supported anionic gold nanoparticle catalysts have been theoretically investigated for their efficacy in activating O2 in aerobic oxidation reactions, limitted studies have been reported owing to the difficulty and complexity of designing these catalysts. Herein, we developed a feasible method for preparing supported anionic gold nanoparticle catalysts using a series of multivacant lacunary polyoxometalates with highly negative charges. Based on experimental findings and theoretical calculations, we confirmed the strong and robust electronic interaction between gold nanoparticles and multivacant lacunary polyoxometalates. In particular, the supported anionic gold nanoparticle catalyst prepared using [SiW9O34]10− acted as an efficient reusable heterogeneous catalyst, showing superior catalytic performance for the oxidative dehydrogenation of piperidone derivatives to the corresponding enaminones and remarkably higher stability than supported gold nanoparticle catalysts without this modification.