Oxidation of Terminal Alkenes to Methyl Ketones
FULL PAPERS
0
.9ꢀ0.1 mmol NH /g and particle size of 35±70 mm (Fluka). Acknowledgements
2
Thermal gravimetric analysis (TGA) was done at Sasol Tech-
nology R&D, South Africa. Solid state NMR was performed
on a Bruker ASX 200 instrument. The Pd content was analyzed
by ICP at Galbraith Laboratories, Knoxville. GC analysis was
done using an HP5890 with a 5% carbowax packed column.
We are grateful to Sasol Technology for support of this research.
PPZ would like to thank Dr. David Phaho for his valuable sug-
gestions.
References
General Procedure for the Amidation of Ester-
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2
n
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The diaminoalkane (62.4 mmol NH ) in methanol (50 ml) was
2
slowly added to silica-supported methyl propylaminoproprio-
1
7, 117.
nate (4 g, 6.24 mmol OCH ) in methanol (50 mL). The mixture
3
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same manner; however, Soxhlet extraction was extended
over 5 days.
[
[
[
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1
[
2
3
3
was added to a phosphomethylated dendrimer (1.0 g) in tol-
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at room temperature under N for 18 h. The reaction mixture
2
changes color from deep maroon to orange-red. Excess solvent
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1
0 mL) followed by ether (3ꢁ5 mL). Residual solvent was re-
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General Procedure for the Oxidation of Terminal
Alkenes to Methyl Ketones
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A mixture of dendrimer-Pd complex (7.5 mmol Pd), substrate
[
[
[
[
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(
(
1.5 mmol) and 5.0±6.0 M tert-butyl hydroperoxide in nonane
1.65 mmol) was placed in a glass autoclave. The autoclave was
immersed in an oil bath set at 558C for 24 h. The autoclave was
cooled to room temperature, and then pressure that built-up
during the reaction period was carefully released. The catalyst
was removed from the reaction mixture by filtration and was
washed with diethyl ether prior to recycling the reaction. The
product was analyzed by FTIR and GC and identified by com-
parison with authentic samples. In cases where the ketone was
isolated, either column chromatography (10:1 hexanes:ethyl
acetate)or distillation was used depending onthe boiling point.
The products were characterized by comparison of spectral
data with authentic samples and with GC of authentic samples.
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8
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