The Mannich Reaction. Mechanistic and Technological Considerations

摘要: HE EARLIEST EXAMPLES of the Mannich reacT tion were published in succession by Tollens and co-workers (1, 2), Petrenko-Kritschenko (3-6), Krosche (7). was first to recognize reaction as a general one, detailed investigation begun 1917. The reviewed Blicke (8), Karbe (9), Nobles (10, 1 l ) , Reichert (12), others (13, 14) it subject recent books (15) arid IHellmann Optiz (16). consists condensation ammonia or primary secondary aminc usually hydrochloride salt, an aldehyde, compound capable supplying one more active hydrogen atoms. As result aminomethyl group generally replaces atom. Products are known “Mannich bases.” A typical condensation, with acetophenone compound, may be illustrated Scheme I. cited excellent review multiple product formation is possible. For example, aminomethylations occur at a-position compounds such previous oiz., 11. Similarly, monoand disubslituted products including position isomers, from