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

Franz       Bracher
doi:10.2174/1570193X16666181204122143
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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[http://dx.doi.org/10.1016/S0040-4039(00)99114-7] 
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DOI https://dx.doi.org/10.2174/1570193X16666181204122143	Print ISSN 1570-193X
Publisher Name Bentham Science Publisher	Online ISSN 1875-6298
Mini-Reviews in Organic Chemistry

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

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