Реферат: Алкилирование енаминов, бета-дикетонов и енаминокетонов

A method is proposed for introducing one, two, or three alkyl substituents into positions 4 and 6 of the cyclohexane-1,3-dione molecule by successive alkylation under the action of strong bases. (+/-)-Angustione (a natural -diketone) has been synthesized.

A Tandem Amino-Cope Rearrangement/Enamine Alkylation Reaction

Steven M. Allin; Martin A. C. Button; Stephen J. Shuttleworth

Source details: Syn.Lett. 1997, 6 725-727.

Document type: Journal

CODEN: SYNLES

Language: EN

CNR: 6086563

Abstract

Thermally induced (3,3)-sigmatropic rearrangement of 3-amino-1,5-diene substrates occurs to give the corresponding enamine products in high yield and with excellent trans:cis enamine selectivity.The enamine produced during the amino-Cope rearrangement has been directly derivatized, representing the first report of a tandem amino-Cope rearrangement/enamine alkylation reaction.The potential of this novel synthetic strategy is outlined.

N-alkylation of enaminones

John V. Greenhill; Ashraf M. Moten

Source details: Tetrahedron 1983, 39 : 20 3405-3408.

Document type: Journal

CODEN: TETRAB

Language: EN

CNR: 5609239

Abstract

The base catalyzed N-alkylation of a series of primary and secondary enaminones has been examined in detail.The enaminone anion was found to be a weak nucleophile.Best results were obtained in tetrahydrofuran or dioxane with sodium hydride and an alkyl iodide.

Alkylation of Ketones and Aldehydes via their Nitrogen Derivatives

James K. Whitesell; Marilyn A. Whitesell

Source details: Synthesis 1983, 7 517-536.

Document type: Journal

CODEN: SYNTBF

Language: EN

CNR: 5572282

Abstract

In this review, methods for the alkylation of the aldehydes and ketones via formation of nitrogen derivatives such as enamines, metallated imines (imine anions), metallated N,N-dialkylhydrazones (N,N-dialkylhydrazone anions), dimetallated oximes (oxime dianions), and metallated O-methyloximes (O-methyloxime anions) are described.Scope, limitations, and advantages or disadvantages of the methods over comparative reactions of enolates are also mentioned.

Intramolecular Photoarylations of N-(Haloaryl)ethyl β-Enaminones

Tammy Tiner-Harding; Patrick S. Mariano

Source details: J.Org.Chem. 1982, 47 : 3 482-485.

Document type: Journal

CODEN: JOCEAH

Language: EN