Catalysts for selective aerobic oxidation under ambient conditions - Advances in Catalytic Activation of Dioxygen by Metal Complexes - page 260

General procedure for sample preparation in acetonitrile. Once the
discovery had been made that was highly active
for thioether oxidation, stock solutions of each component were prepared in
20-mL vials using anhydrous and exposure to light was prevented
by wrapping each vial with aluminum foil. can replace as
a source that acts as a poor halide abstractor. All reagents were dried
using activated molecular sieves after they had been dissolved in anhydrous
Appropriate amounts of each stock solution were added via syringe
to a 20-mL glass vial fitted with a PTFE septum that was first purged with
The atmospheric pressure was adjusted to 1.0 atm and the reactions were
carried out at In all cases, thioethers or sulfoxides were the last
component to be added. The same procedure as above was used except that
the total volume was adjusted using a solvent other than acetonitrile (stock
solutions of each components were prepared in acetonitrile).
Determining the stoichiometry of sulfoxide with respect to The
stoichiometry of sulfoxide with respect to was determined by measuring
consumption using a volumetric method and sulfoxide formation by GC.
Evaluation of the reaction kinetics. The reaction kinetics were evaluated
and curves fit using the Solver subprogram in Microsoft Excel. Rate laws
were determined by varying one component of the system while keeping all
others constant. In order to determine the effect on reaction rate of the
product sulfoxide, DMSO was used as the model for CEESO.
Determining the source of oxygen in product sulfoxide.
The source of oxygen of the product sulfoxide was determined by using
and monitoring the mass abundances by GC-MS. In a separate
experime,t concentrated was added after the addition of thioether.
Substitution of and with other anions. In separate experiments,
was replaced with equimolar amounts of
TMAOH. TBA and TMA

are abbreviations for tetra- n -butylammonium and tetramethylammonium

cations, respectively. In a separate experiment was replaced with an

equimolar amount of
Measuring product selectivity using DMSO. Using similar reaction
conditions as above, DMSO was added after the addition of CEES and the
quantity of DMSO and were monitored by GC.
Determining the effect of DMSO (a product sulfoxide model) on the rate
of catalysis. Varying amounts of DMSO were added to the normal reaction
components to assess the effect on induction period, rate of catalysis, and
self-inhibition.
Assessment of Cu(II) and Fe(III) on rate of CEES oxidation by
Using similar reaction conditions as above in two separate
experiments, two equivalents of and were added before

the addition of CEES.