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6252976 
Book/Book Chapter 
4.1 - The Bimolecular Aliphatic Mannich and Related Reactions 
Kleinman, EF 
1991 
Pergamon 
Oxford 
Comprehensive Organic Synthesis 
893-951 
The Mannich reaction is the prototype of carbon-carbon bond forming reactions that involve the addition of resonance-stabilized carbon nucleophiles to iminium salts and imines. In its original and most widely recognized form, the Mannich reaction consists of three components: (i) ammonia, a primary amine, or a secondary amine; (ii) a nonenolizable aldehyde, usually formaldehyde; and (iii) an active methylene compound. These components condense with concomitant release of water to produce a new base, known as a ‘Mannich base’, in which the active hydrogen is replaced by an aminomethyl group (equation 1). A typical example is the reaction of acetophenone (1), paraformaldehyde (2) and piperidine (3) to produce phenyl β-piperidinoethyl ketone (4; equation 2). The formation of both a carbon-carbon and a carbon-nitrogen bond in this aminomethylation process makes the Mannich reaction an extremely useful synthetic transformation. In addition, Mannich bases have important synthetic applications as intermediates for other compounds. They also occur in natural products such as the alkaloids lycopodine (5), cocaine (6) and elaeocarpine (7) 
Trost, Barry M.