Afaf M. Abdel Hameed

Solar thermochemical reactions: four-component synthesis of polyhydroquinoline derivatives induced by solar thermal energy

The synthesis of polyhydroquinoline derivatives via a four-component unsymmetric Hantzsch reaction induced by solar thermal energy is reported. The process proved to be simple, environmentally friendly, economic and high yielding.

Green and Highly Efficient Synthesis of 2-Arylbenzothiazoles Using Glycerol without Catalyst at Ambient Temperature

A one-pot and clean synthesis of 2-arylbenzothiazoles via the ambient temperature reaction of 2-aminothiophenols and aromatic aldehydes without catalyst in glycerol as a green solvent has been reported.

Simple, Three-Component, Highly Efficient Green Synthesis of Thiazolo[3,2-a]pyridine Derivatives Under Neat Conditions

Abstract Green, highly efficient, three-component syntheses of thiazolo-[3,2-a]pyridine derivatives via reaction of malononitrile, aromatic aldehydes, and 2-mercaptoacetic acid with a catalytic amount of piperidine without solvent with molar ratios of 2:2:1.2 and 2:2.2:1, respectively, has been reported.

Fused Quinoline Heterocycles IX: First Example of a 3,4-Diamino-1H-pyrazolo[4,3-c]quinoline and a 3-Azido-1H-1,2,4,5,6,6a-hexaazabenzo[a]indacene

4-Alkylamino-2-chloroquinoline-3-carbonitriles 4a - c react with NaN3 to give the corresponding tetrazolo[1,5-a]quinoline-4-carbonitriles 5a - c which are converted into 2-amino-quinoline-3-carbonitriles 8a - c by reaction with PPh3 via an iminophosphorane and subsequent hydrolysis. On the other hand, the new 3,4-diamino-1H-pyrazolo[4,3-c]quinoline (11) was prepared by fusion of the aminoquinolines 8a - c with hydrazine hydrate. Diazotization of 11 followed by reaction with NaN3 yielded the novel tetracyclic ring system 3-azido-1H-1,2,4,5,6,6a-hexaazabenzo[a]indacene (13) Graphical Abstract Fused Quinoline Heterocycles IX: First Example of a 3,4-Diamino-1H-pyrazolo[4,3-c]quinoline and a 3-Azido-1H-1,2,4,5,6,6a-hexaazabenzo[a]indacene

Fused quinoline heterocycles VIII. Synthesis of polyfunctionally substituted pyrazolo[4,3- c ]quinol in-4(5 H )-ones

Reaction of 2,4-dichloroquinoline-3-carbonitrile (1) with 4-methylpiperidine gave 2-chloro-4-(4-methylpiperidin-1-yl)quinoline-3-carbonitrile (2). Acid hydrolysis of 2 afforded the corresponding 2-quinolinones 3, which were N-alkylated in DMF to form the 1-methyl, -ethyl and -phenacyl quinolinones 6a–c. Fusion of 6a–c with hydrazine hydrate gave the 3-aminopyrazolo[4,3-c]quinolin-4-ones 8a–c. Diazotisation of 8a,b followed by reaction with sodium azide afforded the novel 3-azidopyrazolo[4,3-c]quinolin-4-ones 9a,b.

Green and efficient synthesis of polyfunctionally substituted cinnolines under controlled microwave irradiation

A convenient, simple and efficient synthesis of polyfunctionally substituted cinnolines has been developed that involves the reaction of ethyl 5-cyano-4-methyl-1-aryl-6-oxo-1,6-dihydropyridazine-3-carboxylate with nitroolefins in dioxane/piperidine under controlled microwave irradiation. The obtained heterocycles are a privileged scaffold in a few natural compounds and in many drugs with a broad spectrum of biological activities.Graphical Abstract

5-Aminouracil as a Building Block in Heterocyclic Synthesis, Part II. One-pot Synthesis of Pyrido[3,2-d:6,5-dʹ]dipyrimidines under Microwave Irradiation without Catalyst

An efficient and direct procedure for the synthesis of pyrido[3,2-d:6,5-dʹ]dipyrimidine derivatives under microwave-assisted conditions is been described. The structures of the products were characterized by elemental analyses, and their IR, 1H NMR, 13C NMR, and MS spectra. Graphical Abstract 5-Aminouracil as a Building Block in Heterocyclic Synthesis, Part II. One-pot Synthesis of Pyrido[3,2-d:6,5-dʹ]dipyrimidines under Microwave Irradiation without Catalyst

First Synthesis and Isolation of the E- and Z-Isomers of Some New Schiff Bases. Reactions of 6-Azido-5-Formyl-2-Pyridone with Aromatic Amines

Some novel Schiff bases have been prepared by reacting 6-azido-5-formyl-2-pyridone 1 with a series of aromatic amines 2a-f. 5-Arylaminomethylene-6-(E)-aryl-iminopyridones 3a-e were obtained by reaction of 1 with 2a-e at room temperature, whereas with 2f, the 6-azido-5-naphthalen-2-yl-iminomethylpyridone derivative 4 was formed. On the other hand, heating 1 with 2a-d at 140-150°C yielded two sets of isomeric products, (E)-3a-d and (Z)-5a-d. Refluxing compounds (Z)-3a,c with hydroxyl-amine in methanol gave the corresponding hydroxyliminopyridones 8a,c. Heating of (E)-3a‑d with excess POCl3 at reflux did not give the expected tricyclic compound 9, but rather the isomeric products (Z)-5a-d were obtained. The structures of all these products have been characterized using IR and 1H- and 13C-NMR spectroscopy.

An efficient and catalyst-free synthesis of N-arylidene-2-arylimidazo[1,2-a]pyridine-3-ylamine derivatives via Strecker reaction under controlled microwave heating

Abstract An efficient one-pot multicomponent reaction of 2-aminopyridine with aromatic aldehydes and either benzoyl cyanide or cyanamide in pyridine under controlled microwave heating afforded N-aryldene-2-arylimidazo[1,2-a]-pyridine-3-ylamine derivatives. The reaction is catalyst free and is of high atom economy.

An efficient multicomponent, one-pot synthesis of Betti bases catalyzed by cerium (IV) ammonium nitrate (CAN) at ambient temperature

Abstract Starting from readily available 2-naphthol, aldehydes, aryl and alkylamines, a variety of Betti bases were efficiently synthesized utilizing a catalytic amount of cerium (IV) ammonium nitrate (CAN) at room temperature. This protocol has advantages of high yield, mild reaction conditions, no environmental pollution, diversity of reactants and simple work up procedure.