A novel and facile synthesis of 2-(cyclohexylamino)-6,7-dihydro-3-aryl-1H-indole-4(5H)-ones via a one-pot multi-component reaction

Tuneable access to indole, indolone, and cinnoline derivatives from a common 1,4-diketone Michael acceptor

A convergent strategy is reported for the construction of nitrogen-containing heterocycles from common substrates: 1,4-diketones and primary amines. Indeed, by just varying the substrates, the substituents, or the heating mode, it is possible to selectively synthesize indole, indolone (1,5,6,7-tetrahydroindol-4-one), or cinnoline (5,6,7,8-tetrahydrocinnoline) derivatives in moderate to excellent yields.

Synthesis of Furocoumarins and Biscoumarins by an Isocyanide-Induced Multicomponent Reaction: Isocyanide as a Masked Amine

The three-component reaction involving chromone-3-carbaldehyde, 4-hydroxycoumarin and cyclohexyl isocyanide produces furocoumarin and biscoumarin derivatives. Formation of the latter compound seems to involve cyclohexylamine. Cyclohexyl isocyanide was found to act as a masked source of cyclohexylamine.

Eco-compatible sonochemical synthesis of 8-aryl-7,8-dihydro-[1,3]-dioxolo[4,5-g]quinolin-6(5H)-ones using green TiO2

A green and an aqueous-mediated sonochemical synthesis of 8-aryl-7,8-dihydro-[1,3]-dioxolo[4,5-g]quinolin-6(5H)-ones from the multi-component reaction of Meldrum's acid, 3,4-methylenedioxy aniline and various aromatic aldehydes is described in the presence of catalytic amount of TiO₂ NPs for the first time using high power sonicator. Initially, TiO₂ NPs has also been synthesized by the biochemical method using leaf extract of Origanum majorana plant as a reducing and capping agent under sonication. Under the sonication, the catalytic activity of synthesized TiO₂ NPs found to be excellent for synthesis of a series of 8-aryl-7,8-dihydro-[1,3]-dioxolo[4,5-g]quinolin-6(5H)-ones with operational simplicity, high yield under green reaction conditions without any environmental issue. The structure of TiO₂ NPs was characterized by FT-IR, SEM, TEM, XRD and EDX studies.

Isocyanide-based multicomponent reactions in the synthesis of heterocycles

In this review, we update our previous presentation, underscoring the recent applications of isocyanides as privileged synthons in the synthesis of various heterocyclic compounds, especially focused on those synthesizedviamulticomponent reactions.

SO3H-functionalized mesoporous silica materials as solid acid catalyst for facile and solvent-free synthesis of 2H-indazolo[2,1-b]phthalazine-1,6,11-trione derivatives

SO₃H-functionalized mesoporous silica materials were used to synthesize 2H-indazolo[2,1-b]phthalazine-1,6,11-trione derivatives in a one-pot three-component condensation reaction.

Bi-SO3H Functionalized Ionic Liquid Based on DABCO: New and Efficient Catalyst for Facile Synthesis of Dihydropyrimidinones

A simple and efficient method for the one-pot Biginelli condensation reaction of aldehydes,β-dicarbonyl compounds, and urea or thiourea employing [DABCO](SO3H)2Cl2as a novel ionic liquid catalyst is described.

One-pot synthesis of acenaphtho[1,2-b]pyrroles in the presence of supported ionic liquid catalyst

Eleven new 8-[(alkyl or aryl)amino]-9-(alkyl or aryl)acenaphtho[1,2-b]pyrroles were synthesized by one-pot reaction of (acenaphthylen-1-yloxy)trimethylsilane, alkyl or aryl aldehyde, ammonium acetate, and aryl or alkyl isocyanide in refluxing DMF.

4-Dimethylamino pyridine-promoted one-pot three-component regioselective synthesis of highly functionalized 4H-thiopyrans via heteroannulation of β-oxodithioesters

A highly convergent and regioselective heteroannulation protocol for the synthesis of hitherto unreported highly substituted 2-amino-4-(aryl/alkyl)-5-(aroyl/heteroaroyl)-3-(cyano/carboalkoxy)-6-methylthio-4H-thiopyran derivatives has been developed. This one-pot three-component domino coupling of β-oxodithioesters, aldehydes, and malononitrile/ethyl or methyl cyanoacetate is promoted by 4-dimethylamino pyridine (DMAP) in solvent (dichloromethane (DCM)) as well as under solvent-free conditions. Systematic optimization of reaction parameters identified that the three-component coupling (3CC) protocol is tolerant to a wide array of functionality providing densely functionalized 4H-thiopyrans in excellent yields. The merit of this cascade Knoevenagel condensation/Michael addition/cyclization sequence is highlighted by its high atom-economy, excellent yields, and efficiency of producing three new bonds (two C-C and one C-S) and one stereocenter in a single operation.