Ni(OAc)₂: a highly efficient catalyst for the synthesis of enaminone and enamino ester derivatives under solvent‐free conditions

Abstract

Ni(OAc) 2 was found to be an efficient catalyst for the synthesis of β-enamino ketones or esters from β-dicarbonyl compounds and amines under solvent-free conditions. The reusability of the catalyst was successfully examined without noticeable loss of its catalytic activity.

Design, synthesis, antimicrobial, antibiofilm evaluation and Z/E-isomerization of novel 6-((arylamino)methylene)benzo[a] phenazin-5(6H)-ones induced by organic solvent

“…17 Several methods for the preparation of enaminones involves reaction between ammonia or primary or secondary amine and 1,3-diketone or 3-keto ester. A straightforward route is provided by the condensation of 1,3-dicarbonyl compounds with amines 18 and by the Mannich reaction of CH(OEt) 3 , ketone, and amine. 19 In recent years, several novel methods for the synthesis of enaminones have been developed.…”

New enaminone sesquiterpenic: TiCl4-catalyzed synthesis, spectral characterization, crystal structure, Hirshfeld surface analysis, DFT studies and cytotoxic activity

“…Various modified synthetic pathways have been reported in literature for the synthesis of β-enaminones using Lewis acids, inorganic acids, ionic liquids, and transition metal catalysts [16]. In addition, other procedures of synthesis were used, such as, microwave [17] and ultrasound irradiations [18].However, α,β-unsaturated ketones react with alkyl-azides upon treatment with Lewis acids via 1,3-dipolar cycloaddition reactions leading to the formation products of expansion resulting from the intermolecular or intramolecular reaction (Azido-Schmidt) [19][20].On the other hand, the catalyst plays an important role in the preparation of 1, 2, 3-triazoline, this later facilitates the conversion to enamine or lactam analogues [21][22].The direct condensation of amines with 1,3-diketone by refluxing in the presence of various catalysts also gives two isomeric enaminones [23][24][25][26][27].According to this bibliographic overview and in continuation of our efforts in the valorization of sesquiterpenes by the synthesis of new compounds [28], we report a simple and selective method for the synthesis of an enaminone based on himachalene using 1,3-dipolar reaction of azide-alkyl with α,β-unsaturated ketone catalyzed by TiCl4.Both spectroscopic and theoretical studies had been undertaken using DFT/B3LYPmethod at 6-31+G(d,p) level. Also, the local reactivity indexes were carried out to investigate the plausible mechanisms for the regioselective synthesis of the compound 2.…”

β‐Enaminone Synthesis from 1,3‐Dicarbonyl Compounds and Aliphatic and Aromatic Amines Catalyzed by Iron Complexes of Fused Bicyclic Imidazo[1,5‐a]pyridine Derived N‐Heterocyclic Carbenes

“…One conventional approach for the synthesis of the β‐enaminone involves the condensation of 1,3‐dicarbonyl compounds with amines. The reaction has been extensively studied with simple transition metal salts, an s ‐block metal salt, the p ‐block metal salts,, and even the f ‐block metal salts , . Apart from these, the usage of simple acids, organocatalysts and the heterogeneous catalysts have been reported for the synthesis of β‐enamino compounds.…”