Deoxygenation of N-Oxides with Triphenylphosphine, Catalyzed by ­Dichlorodioxomolybdenum(VI)

Abstract

Chemoselective deoxygenation of N-oxides was carried out under mild conditions with common phosphines in the presence of dichlorodioxomolybdenum(VI).

Key words

N-oxides - azoxy compounds - molybdenum(VI) - ­nitrones - oxotransfer catalysis

References

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11

PPh₃ only deoxygenates pyridine N-oxides at temperatures over 250 °C. [2b]

18

We have found that in general alkylamines react with dioxomolybdenum chlorides leading to decomposition products some of them have been characterized as alkylammonium polymolybdates: Arnáiz, F. J.; Pedrosa, M. R.; Aguado, R. unpublished results.

19

The complete reduction of 5 required about 15 h.