The reaction of 3‐(1‐imidazolyl)‐2‐alken‐1‐ones with nucleophiles

Abstract

Generally 3‐hetero‐substituted 2‐alken‐1‐ones were prepared from 1,3‐alkanediones, 3‐chloro‐2‐alken‐1‐ones, or conjugated ynones. The preparation of 3‐hetero‐substituted 2‐alken‐1‐ones was subjected to some limitations by these methods. By the reaction of 3‐(1‐imidazolyl)‐2‐alken‐1‐ones (I) and 3‐(3‐oxo‐1‐alkenyl)‐1‐methylimidazolium iodides (II) with nucleophiles, 3‐hetero‐substituted 2‐alken‐1‐ones could be obtained regioselectively in good yield under mild conditions. These results suggested that compounds I and II were concluded to be useful intermediates for the organic synthesis.

A Novel Route to Imidoylbenzotriazoles and Their Application for the Synthesis of Enaminones

“…The available methods for the preparation of enaminones can be classified according to the bond formed (Scheme ). Five approaches form bond a : (i) reactions of 1,3-diketones with amines in the presence of catalysts; , (ii) addition of amines to acylacetylenes; ,20a, (iii) palladium-assisted amination of α-keto olefines , or amination with O -methylhydroxylamines in the presence of base; (iv) additions of amines to 3-oxo-2,3-dihydrothiophene 1,1-dioxides with extrusion of sulfur dioxide; and (v) substitution of a β-functional group, such as alkylthio, imidazolyl, and methoxy . Oxidative cleavage of pyridinium perchlorates with hydrogen peroxide (route xi) provides enaminones via bond d .…”