Russell P. Hughes an American/British chemist, is the Frank R. Mori Professor Emeritus and Research Professor in the Department of Chemistry at Dartmouth College. His research interests are in organometallic chemistry, with emphasis on the chemistry of transition metal interacting with fluorocarbons. His work in this area led to several creative syntheses of complexes between metal complexes and perfluorinated hydrocarbon fragments.
Hughes began his independent scientific career as an Assistant Professor at Dartmouth College in 1976. He was promoted to Associate Professor in 1982, and Professor in 1986. He chaired the department of Chemistry from 1991–1994. In 1999, he was appointed to be the Inaugural Frank R. Mori Professor in the Arts & Sciences. His research has centered on organometallic chemistry, with focus on the chemistry of transition metal interacting with fluorocarbons and the organometallic chemistry of small organic rings. After 35 years of experimental work, he transitioned to computational chemistry and collaborative research.
Metal Complexes of Octafluorocyclooctatetraene (OFCOT)
One of Hughes’ research interests focused on the study of transition metal complexes with octafluorocyclooctatetraene, and the comparison of the structural features of these complexes to the hydrocarbon counterpart of OFCOT cyclooctatetraene. One striking difference in the coordination complexes of OFCOT is that their thermal stability and resistance to undergo dynamic rearrangements in binding geometry are greatly enhanced compared to COT analogs. These differences can be rationalized based on the relative thermodynamic stability of the isomers computed using density functional theory.
First Transition Metal Complexes Containing Perfluorocyclopentadienyl Ligand
In 1992, Hughes and coworkers reported a creative use of flash vacuum pyrolysis to extrude CO from an oxacyclohexadienyl complex led to the first metallocene containing a perfluorinated cyclopentadienyl ring, η5-C5F5. Direct comparison of the ruthenocene to its perfluorocyclopentadienyl analog enabled direct insight into the structural similarities and differences of the two compounds. It was observed that the C5F5 interaction with Ru results in a shorter distance between this ring and Ru, compared to the hydrocarbon analog.
Perfluorobenzyne Complex
In 2001, through dehydrofluorination of an iridium complex bearing perfluorophenyl and hydride groups, Hughes and coworkers synthesized to the first transition metal complex of perfluorobenzyne.
Perfluorocarbene Complexes
In 2005, through an inner-sphere reduction reaction of perfluoroalkyl ligands Hughes and coworkers provided a novel and useful route to difluorocarbene and perfluoroalkylidene complexes. This was followed in 2007 by the synthesis of the first, and so far, the only, example of a carbene ligand bearing two strongly electron withdrawing perfluoroalkyl groups.
The Simplest Fluorocarbon as Ligand
In 2006, Hughes and coworkers showed that even the simplest possible fluorocarbon fragment, CF, stabilized by a triple bond to molybdenum, could be prepared by reduction of a Mo-trifluoromethyl complex.