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Arndt-Eistert synthesis. Isra~Majed. Table of contents. 1 .Objective of this reaction 2. Background 3. Reaction&mechanism 4. Application&recent literature 5. Conclusion 6. References. objectives. 1. To know some information about Arndt-Eistert synthesis
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Arndt-Eistert synthesis Isra~Majed
Table of contents 1.Objective of this reaction 2.Background 3.Reaction&mechanism 4.Application&recent literature 5.Conclusion 6.References
objectives 1.To know some information about Arndt-Eistert synthesis 2.How to make homologated carboxylic acids ortheir derivatives by this reaction
Background • ARNDT-EISTERT SYNTHESIS byFritz Arndtwas born in Hamburg, Germany, It is a simple method for converting an acid into its next higher homologue or to a derivative of the homologous acid, such as an amide or ester.(1)
Reaction&mechanism In the first step of this one-carbon homologation, the diazomethane carbon is acylated by an acid chloride or mixed anhydride, to give an α-diazoketone. The excess diazomethane can be destroyed by addition of small amounts of acetic acid or vigorous stirring. Most α-diazoketones are stable and can be isolated and purified by column chromatography
Reaction &mechanism The key step of the Arndt-Eistert Homologation is the Wolff-Rearrangement of the diazoketones to ketenes, which can be accomplished thermally photochemically or by silver(I) catalysis. The reaction is conducted in the presence of nucleophiles such as water (2)
Application &recent literature Synthesis of Fmoc-β-Homoamino Acids by Ultrasound-Promoted Wolff Rearrangement (3)
Application &recent literature Improved Arndt-Eistert Synthesis of α-Diazoketones Requiring Minimal Diazomethane in the Presence of Calcium Oxide as Acid Scavenger (4)
Conclusion • We are study about this reaction and the mechanism and recent literature
References (1) books.google.ps (2)Zeller, Angew. Chem. Int. Ed., 1975, 14, 32. DOI (3)A. Müller, C. Vogt, N. Sewald, Synlett, 2006, 837-841 (4)V. Pace, G. Verniest, J.-V. Sinisterra, A. R. Alcántara, N . De Kimpe, J. Org. Chem., 2010, 75, 5760-5763.