Chemistry Weekly Seminar - Dr. Paul Hayes

Title: Designing New Ligand Scaffolds to Engender Unusual Reactivity Patterns in Organometallic F-Element Complexes

In an effort to prepare organometallic lanthanide and actinide complexes that feature new and unusual properties, we designed and synthesized several families of NNN-pincer ligands comprised of phosphinimine or pyrazole donors attached to rigid aromatic cores. Rare earth complexes of the ligands have been prepared and notably, diverse reaction behavior, such as cyclometalative C–H bond activation,¹ dearomatization² and functionalization of ligand pyrimidine rings by 1,5-alkyl migration,³ and ring-opening insertion,⁴ has been observed. The evolution of the design of these pincer frameworks has recently yielded a series of thermally stable organolanthanide and organoactinide species that are resistant to cyclometalation.⁵ The synthesis, as well as the small molecule reaction chemistry of the corresponding organometallic complexes, will be discussed in detail.

References:

References:

1.                     Johnson, K. R. D.; Hayes, P. G. Organometallics 2009, 28, 6352-6361.

2.                     Johnson, K. R. D.; Hayes, P. G. Organometallics 2013, 32, 4046-4049.

3.                     Johnson, K. R. D.; Hayes, P. G. Dalton Trans. 2014, 43, 2448-2457.

4.                     Johnson, K. R. D.; Hayes, P. G. Can. J. Chem. 2016, 94, 330-341.

5.                     a) Johnson, K. R. D.; Hannon, M. A.; Ritch, J. S.; Hayes, P. G. Dalton Trans. 2012, 41, 7873-7875. b) Johnson, K. R. D.; Kamenz, B. L.; Hayes, P. G. Organometallics 2014, 33, 3005-3011. c) Zamora, M. T. Johnson, K. R. D.; Hänninen, M. M.; Hayes, P. G. Dalton Trans. 2014, 43, 10739-10750.