Abstract
Selective decarbonylation of p-nitrophenol esters of fatty acids to the corresponding linear α-olefins (LAOs) was achieved using palladium catalysis. After extensive ligand screening, a mixed-ligand system exploiting the trans-spanning diphosphine XantPhos and an N-heterocyclic carbene (IPr) was identified as the most effective in yielding high α-selectivity and high conversions of the ester (>98% selectivity, >90% conversion using 2.5 mol % of PdCl2 and 5 mol % of the ligands, 190 °C, 2-2.5 h). On the basis of insights from modeling at the density functional level of theory, we propose that the mixed-ligand set achieves high α-selectivity by promoting olefin dissociation from the palladium center following β-hydride elimination, which is especially facilitated both by the combined steric bias of the mixed-ligand set and by the ability of the XantPhos ligand to coordinate in both mono- and bidentate fashions.
Original language | English (US) |
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Pages (from-to) | 2956-2964 |
Number of pages | 9 |
Journal | Organometallics |
Volume | 36 |
Issue number | 15 |
DOIs | |
State | Published - Aug 14 2017 |
Bibliographical note
Funding Information:for this work was provided by the Center for Sustainable Polymers at the University of Minnesota, a National Science Foundation (NSF) supported Center for Chemical Innovation (CHE-1413862). The authors acknowledge the Minnesota Supercomputing Institute (MSI) at the University of Minnesota for providing resources that contributed to the research results reported within this paper.
Publisher Copyright:
© 2017 American Chemical Society.