University of Southampton, Southampton, SO17 1BJ, UK.
University of Cambridge, Cambridge, CB3 0FS, UK.
ChemSusChem. 2016 Mar 8;9(5):423-7. doi: 10.1002/cssc.201501264. Epub 2016 Feb 2.
Highly active and selective aerobic oxidation of KA-oil to cyclohexanone (precursor for adipic acid and ɛ-caprolactam) has been achieved in high yields using continuous-flow chemistry by utilizing uncapped noble-metal (Au, Pt & Pd) nanoparticle catalysts. These are prepared using a one-step in situ methodology, within three-dimensional porous molecular architectures, to afford robust heterogeneous catalysts. Detailed spectroscopic characterization of the nature of the active sites at the molecular level, coupled with aberration-corrected scanning transmission electron microscopy, reveals that the synthetic methodology and associated activation procedures play a vital role in regulating the morphology, shape and size of the metal nanoparticles. These active centers have a profound influence on the activation of molecular oxygen for selective catalytic oxidations.
采用连续流动化学技术,利用未封端的贵金属(金、铂和钯)纳米粒子催化剂,可高产率地将蓖麻油氧化为环己酮(己二酸和ε-己内酰胺的前体),实现高效、选择性的有氧氧化。这些催化剂是通过一步原位方法,在三维多孔分子结构中制备的,得到了稳定的多相催化剂。通过详细的分子水平的活性位光谱特性分析,结合像差校正扫描透射电子显微镜,揭示了合成方法和相关的激活程序在调节金属纳米粒子的形态、形状和尺寸方面起着至关重要的作用。这些活性中心对分子氧的活化及其在选择性催化氧化中的应用有深远的影响。