Methyleneiminium salts reviews

The Mannich reaction has been reviewed comprehensively by Blicke (1942), Reichert (1959), Hell-mann and Opitz (1960), and Tramontini (1973). These reviews also include synthetic applications of Mannich bases. Mechanistic studies of the Mannich reaction have been reviewed by Thompson (1968). Some variants of the Mannich reaction have been covered as subtopics in other reviews for example. Layer (1963) and Harada (1970) have reviewed general additions of stabilized carbanions to imines, while Bdhme and Haake (1976) have reviewed similar additions to methyleneiminium salts. In more specific reviews, Pai and coworkers (1984) have summarized stabilized carbanion additions to 3,4-dihy-droisoquinolines and 3,4-dihydroisoquinolinium salts in connection with the total synthesis of protober-berines and phthalide isoquinolines, and Evans et al. (1982) " have analyzed the stereochemical aspects of ester enolate and silyl ketene acetal additions to imines. 

Pioneering investigations by Bdhme et al. into the synthesis, properties and reactions of preformed iminium salts have provided much of the basis for their recent applications in organic synthesis. These and related investigations are described in his extensive review on Methyleneiminium Salts , covering woric up to the early 1970s. 

The synthesis of a-halogenated imino-compounds has been reviewed, and the preparation of chloro(ethoxycarbonyl)methyleneiminium salts as versatile intermediates in heterocyclic synthesis has been demonstrated. ... 

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