We are synthetic inorganic/organometallic chemists with an interest in main group and catalytic chemistry. A major theme of our research is the catalytic transformation of organic molecules by transition metal complexes. We are particularly interested in the polymerization of olefins and the enantioselective hydrogenation of unsaturated molecules—two areas of tremendous economic importance. An unusual aspect of our work is the use of heterocyclic inorganic molecules as scaffolds for ligands in catalytically-active complexes. The bis(phosphine)ethanediylnickel dichloride complex, shown below, shows good activity in the polymerization of olefins.

We have synthesized numerous inorganic heterocycles with four-membered (PN)2 , (SiN)2 or (PN2Si) rings, like the ones shown in the ligand below. These ambidentate molecules exhibit a variety of coordination modes and may serve as both hard- and soft-donor ligands. To characterize the compounds we synthesize, we make extensive use of multinuclear NMR techniques and single-crystal X-ray diffraction studies. Most of the complexes we synthesize are screened for their catalytic activities in our laboratories before being sampled to our industrial collaborators.

REPRESENTATIVE PUBLICATIONS

Moser, D.; Grocholl, L.; Stahl, L.; Staples, R. J. “Bis( tert -butylamido)- and bis(arylamido)cyclodiphosph(III)azane complexes of titanium, vanadium, zirconium and hafnium: ligand substituent effects and coordination number” J. Chem. Soc. Dalton Trans., 2003, 1402–1410.

Schranz, I.; Lief, G. R.; Midstokke, S. J.; Stahl, L. “Inorganic-Heterocyclic Bis(phosphines): Syntheses and Structures of a 1,2-Bis (diazasilaphosphetidino)ethane and Its Nickel, Molybdenum and Rhodium Complexes” Inorg. Chem., 2002, 41, 6919–6927.

Haagenson, D. C.; Moser, D. F.; Stahl, L.; Staples, R. J. “Syntheses and Structures of P -(amino)- P -(chalcogeno)- and P -(amino)- P -(imino)- diazasilaphosphetidines and Their Group 12 and 13 Metal Compounds” Inorg. Chem. 2002, 41, 157–162.

Lief, G. R.; Carrow, C. J.; Stahl, L.; Staples, R. J. “Mono- and dinickellaazaphosphiranes of mono- and bis(amido)cyclodiphosph(III)azanes” Chem. Commun. 2001, 1562–1563.

Moser, D. F.; Carrow, C. J.; Stahl, L.; Staples, R. J. “Titanium Complexes of Bis(1°-amido)cyclodiphosph(III)azanes and Bis(1°-amido)cyclodiphosph(V)azanes: Facial versus Lateral Coordination” J. Chem. Soc., Dalton Trans. 2001, 1246–1252.

Stahl, L. “Bis(amido)cyclodiphosphazane Compounds with Main Group Element Incorporation” Coord. Chem. Rev., 2000, 210, 203 – 250.