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Mini-Reviews in Organic Chemistry

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ISSN (Online): 1875-6298

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Review Article

Dimethylformamide Acetals and Bredereck’s Reagent as Building Blocks in Natural Products Total Synthesis

Author(s): Franz Bracher*

Volume 17, Issue 1, 2020

Page: [47 - 66] Pages: 20

DOI: 10.2174/1570193X16666181204122143

Price: $65

Abstract

Dimethylformamide acetals and Bredereck’s reagent (tert-butoxy-bis(dimethylamino) methane) are versatile C1 building blocks due to their ability to undergo condensation reactions with CH-acidic methyl and methylene moieties. Subsequent modulation of the resulting condensation products enables the preparation of open-chain products like aldehydes, ketones, enones, enol ethers, methyl groups, and, most important in alkaloid total synthesis, the annulation of heterocyclic rings like pyridines, pyridine-N-oxides, bromopyridines, aminopyridines, aminopyrimidines, pyrroles and chromenones. In certain cases, these reagents can act as alkylating agents. The applications of these building blocks in natural products total synthesis are reviewed here.

Keywords: Alkaloid, annulation, Bredereck's reagent, condensation, cyclization, dimethylformamide acetal, indole, naphthyridine, pyridoacridine, total synthesis.

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