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Rhodium-Catalyzed Branched-Selective Alkyne Hydroacylation: A Ligand-Controlled Regioselectivity Switch


  • We thank the EPSRC and Xunta de Galicia (Angeles Alvariño contract and an Estadías: 2009/188 and 2010/163 to CGR) for support of this work. Additional thanks to Diamond Light Source for beamtime on I19 (MT1858), and Kirsten E. Christensen and David R. Allan for assistance.


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It's all in the ligand: By choice of the appropriate diphosphine ligand a previously linear-selective alkyne hydroacylation process can be “switched” to be highly branched-selective (see scheme, l=linear, b=branched). Structural data for the ortho-iPr-dppe–rhodium catalyst suggest restricted rotation of the phosphine aryl units may be responsible for the observed selectivity.