Synthesis,crystal structure of some new 2‐(4‐methylbenzoylimino)‐3‐aryl‐4‐methyl‐1,3‐thiazolines

An efficient, straightforward synthesis of some new 2‐(4‐methylbenzoylimino)‐3‐aryl‐4‐methyl‐1,3‐thiazolines ( 2a‐i ) is described. The methodology involves the cyclization of 1‐(4‐methylbenzoyl)‐3‐arylthioureas with acetone in the presence of bromine and triethylamine. The structures were confirmed by spectroscopic data, elemental analyses and in one case ( 2i ) by the single crystal X‐ray diffraction data.     

One‐pot synthesis of 2‐acylimino‐3‐aryl‐1,3‐thiazoline derivatives in aqueous media

The one‐pot two‐step synthesis for acyliminothiazolines by treatment of N,N'‐substituted thioureas with α‐bromocarbonyl compounds under aqueous media was described. Compared to classical reaction in organic solvents, this method consistently has the advantages of short reaction time and being environmentally friendly.     

One‐pot three‐component synthesis of 2‐substituted 4‐aminoquinazolines

A facile and rapid synthesis of the title compounds via one‐pot reaction of 2‐aminobenzonitrile, orthoesters and ammonium acetate under solvent‐free and microwave condition is described.     

Tandem One‐pot Synthesis of Polysubstituted 1,3‐Thiazine Derivatives

A tandem one‐pot synthesis of polysubstituted 1,3‐thiazines has been developed by reacting with cyanoacetamide and isothiocyanate derivatives to give rise to 2‐cyano‐3‐mercaptoacrylamides, which are trapped in situ by various aldehydes or diversely substituted ketones through intermolecular cyclization, providing polysubstituted 1,3‐thiazine derivatives in short reaction times with good to excellent yields. The salient features of this novel protocol are operational simplicity, accessing the desired products from the readily available starting materials and easy of product isolation and may find wide spread applications in medicinal chemistry.     

Synthesis and characterization of 4‐aryl‐5‐(1‐aryl‐2‐methyl‐2‐nitropropyl)‐1,2,3‐selenadiazoles

The synthesis of a new set of selenadiazoles, 4‐aryl‐5‐(1‐aryl‐2‐methyl‐2‐nitropropyl)‐1,2,3‐selenadiazoles ( 4 ) derived from 2‐[4‐methyl‐4‐nitro‐1,3‐diarylpentylidene]‐1‐hydrazinecarboxamide ( 3 ) has been reported. THF has been found to be the solvent of choice for this reaction. Structural features of 3 and 4 have been analyzed by NMR and X‐ray techniques.     

Facile One‐pot Synthesis of Substituted Dihydropyrrol‐2‐ones via Four‐component Domino Reaction of Amines,Dialkyl Acetylenedicarboxylates and Formaldehyde

A mild and efficient method for the one‐pot synthesis of substituted dihydropyrrol‐2‐one derivatives is described via four‐component domino reaction of amines, dialkyl acetylenedicarboxyaltes and formaldehyde in the presence of 1‐methyl‐2‐oxopyrrolidinium hydrogen sulfate ([Hpyro][HSO₄]) as ionic liquid catalyst. This facile approach proceeded smoothly in good to high yields and pure products are separated from the reaction mixture by simple filtration.     

Catalyst‐free Synthesis of Tetrahydroacenaphtho[1,2‐b]indolone Derivatives via One‐pot Four‐component Reaction

A simple and efficient one‐pot synthesis of tetrahydroacenaphtho[1,2‐b]indolone derivatives via four‐component reaction of 5,5‐dimethylcyclohexane‐1,3‐dione (dimedone), arylamines, acenaphthoquinone, and active methylene compounds under catalyst‐free conditions is described. The reactions were carried out under mild conditions using ethanol as solvent. Advantages of this method include simple experimental and workup procedure, readily available starting materials, and high yields.     

A High Performance Route for the Synthesis of Dihydropyrrolo[1,2‐f]phenanthridine Scaffolds by using a One‐pot Four‐component Reaction

Synthesis of a series pyridine containing dihydropyrrolo core fused phenanthridines by a one‐pot four‐component reaction in an efficient route is reported. This report contains the reaction of pyridinecarbaldehydes, malononitrile, and phenanthridine in the presence of alkyl isocyanides.     

Efficient One‐pot Synthesis of Alkyl 3‐(alkyl)‐4‐methyl‐2‐thioxo‐2,3‐dihydrothiazole‐5‐carboxylates in a Multi Component Reaction

A simple and efficient one‐pot synthesis of alkyl 2‐(alkyl)‐4‐methyl‐2‐thioxo‐2,3‐dihydrothiazole‐5‐carboxylates from the reaction of primary alkylamines and carbon disulfide in the presence of 2‐chloro‐1,3‐dicarbonyl compounds is described. This new protocol has several advantages such as lack of necessity of the catalyst, good yields, mild conditions and short times for reaction.     

An Efficient and Facile Synthesis of 5‐Amino‐3‐methyl‐7‐aryl‐1,3‐dihydroisobenzofuran‐4,6‐dicarbonitrile Derivatives Under Mild Conditions

This article describes an efficient approach for the synthesis of 5‐amino‐3‐methyl‐7‐aryl‐1,3‐dihydroisobenzofuran‐4,6‐dicarbonitrile derivatives from the reaction of aromatic aldehyde, 2‐methyltetrahydrofuran‐3‐one, and malononitrile under mild conditions. This is a simple and facile process to structure this important heterocyclic compounds. The other advantages of this approach are rapid reaction rate, high yield, and simple procedure. This article provided a good method for the synthesis of 1,3‐dihydroisobenzofuran derivatives.     

BTADCI Promoted One‐pot Synthesis of 14‐aryl‐14H‐dibenzo [a,j] Xanthenes

A convenient eco‐friendly one‐pot synthesis of 14‐aryl‐14H‐dibenzo [a, j] xanthenes were developed by the condensation of aromatic aldehydes and β‐naphthol with BTADCI (Benzyltrimethylammonium dichloroiodate) as catalyst under solvent free conditions and microwave irradiation with much more rate accelerations and afford very good yields. Developed protocols involve mild reaction conditions, simple isolation of derivatives with inexpensive reagents.     

Unexpected One‐pot Synthesis of Novel 2‐Aminopyrimidine‐4‐ones under Microwave Irradiation

One‐pot, three‐component condensation of guanidine, ethylbenzoylacetate and various aromatic aldehydes in the presence of NaHCO₃ have been investigated by microwave irradiation. The aromatic aldehydes bearing electron‐withdrawing groups undergo condensation with guanidine and ethylbenzoyl‐acetate to afford ethyl‐2‐amino‐4‐aryl‐1,4‐dihydro‐6‐phenylpyrimidine‐5‐carboxylate derivatives via Biginelli reaction. However, reaction of the aromatic aldehydes having electron‐releasing groups with guanidine and ethylbenzoylacetate did not give the corresponding dihydropyrimidines. Instead, novel 2‐amino‐5‐benzoyl‐5,6‐dihydro‐6‐arylpyrimidine‐4(3H)‐ones were obtained via an unexpected mechanism.     

聚合物负载磺酸催化的三组分反应合成1-酰胺烷基-2-萘酚

聚合物负载磺酸，一种环境友好的固体酸催化剂，可以有效地催化2-萘酚、脲或酰胺和醛的三组分“一锅”反应生成1-酰胺烷基-2-萘酚。该方法得率高，操作简单。     

An Efficient One‐pot Synthesis of 2‐Amino‐5‐arylidenethiazol‐4‐ones Catalyzed by MgO Nanoparticles

A mild and efficient protocol for the synthesis of 2‐amino‐5‐arylidene‐1,3‐thiazol‐4(5H)‐ones is reported by three component reaction of aldehydes, rhodanine and secondary amines in the presence of magnesium oxide nanoparticles as heterogeneous nanocatalyst in good yields and short reaction times.     

New domino‐reaction for the synthesis of N4‐(5‐aryl‐1,3‐oxathiol‐2‐yliden)‐2‐phenylquinazolin‐4‐amines and 4‐[4‐aryl‐5‐(2‐phenylquinazolin‐4‐yl)‐1,3‐thiazol‐2‐yl]morpholine

The model morpholine‐1‐carbothioic acid (2‐phenyl‐3H‐quinazolin‐4‐ylidene) amide (1) reacts with phenacyl bromides to afford N⁴‐(5‐aryl‐1,3‐oxathiol‐2‐yliden)‐2‐phenylquinazolin‐4‐amines (4) or N⁴‐(4,5‐diphenyl‐1,3‐oxathiol‐2‐yliden)‐2‐phenyl‐4‐aminoquinazoline ( 5 ) by a thermodynamically controlled reversible reaction favoring the enolate intermediate, while the 4‐[4‐aryl‐5‐(2‐phenylquinazolin‐4‐yl)‐1,3‐thiazol‐2‐yl]morpholine ( 8 ) was produced by a kinetically controlled reaction favoring the C‐anion intermediate. ¹H nmr, ¹³C nmr, ir, mass spectroscopy and x‐ray identified compounds ( 4 ), ( 5 ) and ( 8 ).     

One‐pot solvent‐free synthesis of novel functionalized ethyl 2‐(alkylimino)‐4‐methyl‐3‐(alkanoyl)‐2,3‐dihydrothiazole‐5‐carboxylates

A green and efficient one‐pot two‐step synthesis of ethyl 2‐(alkylimino)‐4‐methyl‐3‐(alkanoyl)‐2,3‐dihydrothiazole‐5‐carboxylates from the reaction between acyl chlorides, ammonium thiocyanate, primary alkylamines, and ethyl 2‐chloroacetoacetae under mild, solvent‐ and catalyst‐free conditions at room temperature is presented. This efficient and straightforward technique gave the expected products in good to high yields in 2–4 hr without the creation of any by‐product in all reactions.     

An Efficient Synthesis of N‐Substituted‐3‐aryl‐3‐(4‐hydroxy‐6‐methyl‐2‐oxo‐2H‐pyran‐3‐yl)propanamides by Four‐Component Reaction in Aqueous Medium

A mild and efficient synthesis of N‐substituted‐3‐aryl‐3‐(4‐hydroxy‐6‐methyl‐2‐oxo‐2H‐pyran‐3‐yl)propanamides via four‐component reaction of an aldehyde, amine, Meldrum's acid, and 4‐hydroxy‐6‐methyl‐2H‐pyran‐2‐one in the presence of benzyltriethylammonium chloride (TEBAC) in aqueous medium is described. This method has the advantages of accessible starting materials, good yields, mild reaction conditions, and begin environmentally friendly.     

A Novel Iron‐catalyzed One‐pot Synthesis of 3‐Amino‐1,2,4‐triazoles

A novel one‐pot synthesis of 3‐amino‐1,2,4‐triazole developed via iron (III) catalyzed route is reported. The new method is more efficient, simple, and convenient and presents a concise new strategy for the synthesis of 3‐amino‐1,2,4‐triazole derivatives. The iron (III) complex intermediate assisted in the intramolecular bond cyclization owing to its Lewis acidity or oxidizing properties. A series of aromatic nitriles bearing different electron‐donating and electron‐withdrawing groups substituted at para and/or ortho positions were also investigated. The position of the substituents affected the yield of the final compound, with the para‐substituted substrates giving relatively higher yields.     

An Efficient One‐pot Three‐component Method for the Synthesis of 5‐Amino‐3‐(2‐oxo‐2H‐chromen‐3‐yl)‐7‐aryl‐7H‐thiazolo[3,2‐a]pyridine‐6,8‐dicarbonitriles

A facile, convenient, and adequate method has been developed for the synthesis of novel 5‐amino‐3‐(2‐oxo‐2H‐chromen‐3‐yl)‐7‐aryl‐7H‐thiazolo[3,2‐a]pyridine‐6,8‐dicarbonitriles ( 6 ) by employing 2‐(4‐(2‐oxo‐2H‐chromen‐3‐yl)thiazol‐2‐yl)acetonitrile ( 3 ) as an important precursor. Initially, we have synthesized the target compounds in a stepwise manner and then approached a tandem method to examine the feasibility of one‐pot method. Subsequently, one‐pot three‐component protocol has been established for the synthesis of title compounds by the reaction of 3 with benzaldehyde and malononitrile in refluxing ethanol engender a new six‐membered thiazolo[3,2‐a] pyridine as a hybrid scaffold. Reaction conditions were optimized for this reaction and a broad substrate scope with various aryl and heteroaryl aldehydes make this protocol very practical, attractive, and worthy. Mechanistic aspects for the formation of these compounds were outlined comprehensively. Characterization of these newly synthesized compounds was achieved by means of IR, ¹H NMR, ¹³C NMR, and HRMS.