90
KHENKIN, ROSENBERGER, AND NEUMANN
and cycloctane in acetone were mixed no product was
formed.
ACKNOWLEDGMENT
This research was supported by the Basic Research Foundation admin-
istered by the Israel Academy of Sciences and Humanities.
The third pathway is for the acyl peroxo radical to react
with aldehyde to form an acyl oxo radical and carboxylic
acid. The acyl oxo radical can then he decomposed to CO2
and acetone (via the alkyl radical and dioxygen in the pres-
ence of acid) (42). We have already described above the
experiment showing that indeed about 10–12% of the
aldehyde eventually decomposes to acetone and CO2. In
the fourth pathway, two peroxo radicals may combine to
form oxygen and acid. The existence of this pathway may
be inferred in so much as 70% of isobutyraldehyde was
nonproductively decomposed. In the final pathway, the acyl
peroxo radical could react with a vanadium (molybdenum)
center in the polyoxometalate to yield a vanadium-centered
peroxo species. The intermediacy of a polyoxometalate per-
oxo compound POM–O–O–C(O)CH(CH3)2 was more dif-
ficult to prove conclusively. Its formation may, however, be
inferred from the inhibition of the alkane oxidation at high
H5PV2Mo10O40 concentrations. The H5PV2Mo10O40 com-
pound, although catalyzing formation of the acyl peroxo
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