Introduction

The unexpected influence of aryl substituents in N-aryl-3-oxobutanamides on the behavior of their multicomponent reactions with 5-amino-3-methylisoxazole and salicylaldehyde

“…The Lewis acid catalyst activates the carbonyl group in salicylaldehyde ( 2 ), which is subsequently able to interact with the 4-CH nucleophilic center of the aminoisoxazole 1 and not only with the exocyclic NH 2 group [26]. The resulting adduct 10 (Scheme 4, pathway C) then reacts with carboxamide 3a forming intermediate 11 which can lose a water molecule in two different ways: either by elimination occurring at room temperature leading to dihydroisoxazolo[5,4- b ]pyridine 5a or through nucleophilic substitution involving the phenolic hydroxy group under ultrasonic activation furnishing the oxygen-bridged compound 6a .…”

Unusual in Water Multicomponent Reaction of 3-Amino-5-methylpyrazole, Acetylacetone and Aldehyde

“…Azolopyrimidines having a nodal nitrogen are excellent objects for both, either multicomponent [2] or sequential synthesis [3] (Scheme 1); both of them presume use of diverse aminoazoles 1 (3-amino-1,2,4-triazole [4], 3-aminopyrazole [5], 5-aminotetrazole [6] Another important trend in modern synthesis is "green chemistry" [7]; among its principles use of "green" solvents like water appeared to be highly effective [8].…”

The Synthesis and Molecular Crystalline Structure of Ethyl-1- Acetyl-3-(4-Chlorophenyl) -2,2-Dicyanocyclopropane Carboxylate

“…It should be noted that multicomponent reactions, involving simultaneous interaction of, at least, three compounds and forming one final product together with parts of all the initial components, contribute to the development of new methods to synthesize polyfunctional carbo-and hetero-cycles with useful properties. Typically, the developed multicomponent reactions proceed in one-step ("one-pot"), by using commercially available substrates and reagents, which significantly reduce the cost of final products as well as harmful environmental consequences of the synthesis occurrence [1][2][3][4][5]. A large number of multicomponent reactions have been discovered, analyzed and described.…”