Functional Models for Rhodium‐Mediated Olefin‐Oxygenation Catalysis

Abstract

Oxygenation of C-H and C=C bonds of hydrocarbons with H2O2 and O2 is an important industrial method to convert mineral oil into useful chemicals. Despite their enormous economic impact, these reactions are still not fully understood. In the early 1970s, the potential of Rh and Ir complexes for olefin oxygenation was investigated intensively. Simple inorganic salts of these metals proved to be rather useless for industrial application when compared with the traditional Wacker system. However, the appropriate choice of ligands allows the stepwise oxidation of olefins at Rh and Ir. These systems are therefore useful to study mechanistic details of substrate binding and C-O bond formation at the catalytic metal center. Insight from these model studies helps in understanding the catalytic reactions at these (and possibly other) metal centers. Further insight into the differences between the Rh system and traditional Wacker-type oxidation at Pd may lead to useful applications.

Gas phase chemistry of neutral metal clusters: Distribution, reactivity and catalysis

“…Since processes on metal oxide catalytic surfaces are so complex, a fundamental understanding of these catalytic mechanisms is still not available, and thus a rational approach to effective catalyst synthesis and application is difficult. Gas phase studies of metal oxide clusters and their reaction behavior can help to understand the mechanism of elementary reactions in oxidation-reduction catalytic processes under isolated, controlled, reproducible, and theoretically predicated conditions [52,[108][109][110][111][112][113]. Adapted from Refs.…”

[IrCl{N(CHCHPtBu2)2}]−: a versatile source of the IrI(PNP) pincer platform

“…in the context of alkene oxygenation. 30 3 ) which was synthesized in the solid state and was in turn not spectroscopically examined. 34 Hence, a full set of spectroscopic and structural data for this class of compounds is surprisingly not available.…”

Oxidative Coupling of Aromatic Substrates with Alkynes and Alkenes under Rhodium Catalysis

“…On the other hand, the Rh III /Rh I process, as well as Pd II /Pd 0 , is also known to be applicable to organic oxidation reactions 1a. 8 Around 40 years ago, the rhodium‐catalyzed oxidation of olefins was extensively investigated9 in addition to a well‐known palladium‐catalyzed version, that is, the Wacker process. Since then, the rhodium catalyst systems for oxidation have been less explored than those with palladium.…”