A novel Ru(II) organometallic catalyst with highly ordered cage-like mesoporous structure was prepared by coordinating the Ru(II) with the PPh2-ligand incorporated into the FDU-12 support (Ru–PPh2-FDU-12). During water-medium isomerization of 1-phenyl-3-buten-1-ol, the Ru–PPh2-FDU-12 exhibited almost the same activity and selectivity as the corresponding RuCl2(PPh3)3 homogenous catalyst and could be used for at least 5 repetitions, showing good potential for industrial application. The excellent performance of the Ru–PPh2-FDU-12 could be attributed to the high and uniform dispersion of the Ru(II) active sites on the FDU-12 support, the large size of both the pore entrance and pore cages, which facilitated the diffusion, the adsorption and the transformation of organic substrates on the catalyst surface. The decrease in the activity of the Ru–PPh2-FDU-12 after being used for 5 times could be mainly attributed to the decrease in the pore entrance size and the pore cage size rather than the leaching of the Ru(II) active species from the FDU-12 support.
