Emde Degradation

H. Emde, Ber. 42, 2590 (1909); Ann. 391, 88 (1912).

Modification of the Hofmann degradation, q.v., method for reductive cleavage of the carbon-nitrogen bond by treatment of an alcoholic or aqueous solution of a quaternary ammonium halide with sodium amalgam. Also used as a catalytic method with palladium and platinum catalysts. The method succeeds with ring compounds not degraded by the Hofmann procedure:

Reviews: A. Birch, Org. React. 7, 143 278 (1953); F. Möller, Houben-Weyl 11/1, 973 (1955); Z. Spialter, J. A. Pappalardo, Acyclic Aliphatic Tertiary Amines (Macmillan, New York, 1965) pp 79-81. Photodegradation: V. Partail, Helv. Chim. Acta 68, 1952 (1985). Synthetic applications: J. G. Cannon et al., J. Med. Chem. 18, 110 (1975); J. Lévy et al., Tetrahedron Asymmetry 8, 4127 (1997).