McFadyen-Stevens reaction

The McFadyen-Stevens reaction is a chemical reaction best described as a base-catalyzed thermal decomposition of acylsulfonylhydrazides to aldehydes.Ref|McFadyen1936Ref|Mosettig1954

Dudman has developed an alternative hydrazide reagent.Ref|Dudman1980

Reaction mechanism

The mechanism of the McFadyen-Stevens reaction is still under investigation. Two groups have independently proposed a heterolytic fragmentation mechanism.Ref|Brown1958Ref|Campaigne1959 The mechanism involves the deprotonation of the acyl sulfonamide followed by a 1,2-proton migration to give the alkoxide (3). The collapse of the alkoxide results in the fragmentation producing the desired aldehyde (4), nitrogen gas, and an aryl sulfinate ion (5).

Martin "et al." have proposed a different mechanism involving an acyl nitrene.Ref|Martin1974

References

# McFadyen, J. S.; Stevens, T. S. "J. Chem. Soc." 1936, 584.
# Mosettig, E. "Org. React." 1954, "8", 232-240. (Review)
# Dudman, C. C. "et al." "Tetrahedron Lett." 1980, 4645.
# Brown, V. M.; Carter, P. H.; Tomlinson, M. "J. Chem. Soc." 1958, 1843.
# Campaigne, E.; Thompson, R. L.; Van Werth, J. E. "J. Med. Chem." 1959, "1", 577.
# Martin, S. B.; Craig, J. C.; Chan, R. P. K. "J. Org. Chem." 1974, "39", 2285 - 2289. (DOI|10.1021/jo00929a600)

ee also

* hydrazide