Recent development in preparation reactivity and biological activity of enaminoketones and enaminothiones and their utilization to prepare heterocyclic compounds

A variety of β-enamino ketones and esters have been synthesized in high to exellent yields by reacting β-dicarbonyl compounds with amines in the presence of a catalytic amount of indium tribromide. The reaction proceeds smoothly at room temperature in a short reaction time under solvent-free conditions.

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A General and Efficient Method for the Preparation of β-Enamino Ketones and Esters Catalyzed by Indium Tribromide

A mild, efficient and environmentally friendly method for the regio- and chemoselective synthesis of enaminones using Bi(TFA)3 as a reusable catalyst in aqueous media

A new reaction for the preparation of enaminones has been discovered. This method employs β-amino acids as starting materials to allow diversification as well as incorporation of chirality. The β-amino acids, once converted to ynones, are readily cyclized to the desired six-membered enaminone via a two-step, one-pot protocol. Although disguised as a 6-endo-dig cyclization, the reagents employed in the transformation play a direct role in bond making and bond breaking, thus changing the mode of addition.

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Amino Acid-Derived Enaminones: A Study in Ring Formation Providing Valuable Asymmetric Synthons

Reformatsky reactions with N-arylpyrrolidine-2-thiones: synthesis of tricyclic analogues of quinolone antibacterial agents

Efforts in our laboratories to devise a general approach to the synthesis of alkaloids focus on the versatile reactivity of enaminones and related compounds containing the structural unit N-CaC-Z (Za COR, CO2R, CN, NO2 ,S O 2Ar, etc.). This lecture presents an overview of our research with these useful building blocks. Themes to be elaborated include chemo- selectivity and diastereoselectivity in reactions of enaminones, and the challenge of controlling absolute stereochemistry.

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Andrew S. Parsons

Papers

Enaminones: versatile intermediates for natural product synthesis*

Chemoselective reactions of vinylogous amides, and the synthesis of two peripentadenia alkaloids

Synthesis of two pyrrolidine alkaloids, peripentadenine and dinorperipentadenine

Enaminones: Versatile Intermediates for Natural Product Synthesis

Synthesis of Two Pyrrolidine Alkaloids, Peripentadenine (Ia) and Dinorperipentadenine (Ib).