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Updated: May 17, 2026

The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes
Published on: April 10, 2015
Spiroketal-based phosphorus ligands for highly regioselective hydroformylation of terminal and internal olefins
Xiaofei Jia1, Zheng Wang, Chungu Xia
1State Key Laboratory of Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, 18 Tianshui Middle Road, Lanzhou 730000, P.R. China.
Abstract:
A new class of bidentate phosphoramidite ligands, based on a spiroketal backbone, has been developed for the rhodium-catalyzed hydroformylation reactions. A range of short- and long-chain olefins, were found amenable to the protocol, affording high catalytic activity and excellent regioselectivity for the linear aldehydes. Under the optimized reaction conditions, a turnover number (TON) of up to 2.3×10(4) and linear to branched ratio (l/b) of up to 174.4 were obtained in the Rh(I)-catalyzed hydroformylation of terminal olefins. Remarkably, the catalysts were also found to be efficient in the isomerization-hydroformylation of some internal olefins, to regioselectively afford the linear aldehydes with TON values of up to 2.0×10(4) and l/b ratios in the range of 23.4-30.6. X-ray crystallographic analysis revealed the cis coordination of the ligand in the precatalyst [Rh(3d)(acac)], whereas NMR and IR studies on the catalytically active hydride complex [HRh(CO)(2)(3d)] suggested an eq-eq coordination of the ligand in the species.
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