Experimental and Theoretical Investigation of One‐pot Synthesis of 2‐Amino‐4H‐chromenes Catalyzed by Basic‐functionalized Ionic Liquids

An efficient and environmentally benign procedure for the reactions of three components condensation of salicylaldehyde and two different CH acids to give 2‐amino‐4H‐chromenes catalyzed by a series of basic‐functionalized ionic liquids was reported. The most possible reaction pathway was proposed for the first time by performing density functional theory (DFT) calculations. Both cation and anion of [Bmim]OH have a cooperative effect on the reaction. [Bmim]⁺ increases the electrophilicity of salicylaldehyde via intermolecular hydrogen bonds, while OH^? deprives proton of two CH acids to strengthen their nucleophilic ability.     

One‐pot PTC synthesis of polyfused pyrazoles

Thienopyrazole 2 , 3 , 5 , or 6 and thienopyrazolothiazepine 7, 9 , and 11 derivatives were prepared via the reaction of the 3‐aminopyrazoline‐5‐one 1 with CS₂ and different molar ratio of a variety of halo compounds having an active methylene under PTC conditions. Also, treatment of 1 with CS₂ and alcoholic KOH in 2:1:1 molar ratio afforded dipyrazolopyridine derivatives 12 and 14 . On other hand, the pyrazolothiadiazineone derivative 13 was obtained by treating compound 1 with CS₂ and alcoholic KOH in 1:2:2 molar ratio. Under PTC conditions, compound 1 , CS₂, and ethyl cyanoacetate or malononitrile to gave the pyrazolopyridine derivatives 16 and 17 . Coupling of compound 1 with diazonium acetates afforded the hydrazone derivatives 18a,b , which were oxidized with bromine to give pyrazolotriazoles 19a,b or cyclized with aldehydes to give pyrazolotriazine derivatives 20a–e . Bromination of compound 1 afforded monobromopyrazole derivative 21 , which could be condensed to a dipyrazolopyrazindione 23 . Finally, the dibromopyrazole derivative 22 was cyclized with 2‐mercaptoethanol or o‐phenylenediamine to give the spiropyrazoles 24a,b . © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:211–217, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10129     

N,N‐dimethylamino‐functionalized basic ionic liquid catalyzed one‐pot multicomponent reaction for the synthesis of 4H‐benzo[b]pyran derivatives under solvent‐free condition

A simple, clean, and environmentally benign three‐component process for the synthesis of 4H‐benzo[b]pyran derivatives using basic ionic liquid N,N‐dimethylaminoethylbenzyldimethylammonium chloride ([PhCH₂Me₂N⁺CH₂CH₂NMe₂]Cl⁻) as an efficient catalyst under solvent‐free condition is described. A wide range of aromatic aldehydes easily undergoes condensation with malononitrile and 5,5‐dimethylcyclohexane‐1,3‐dione (dimedone) under solvent‐free condition to afford the desired products of good purity in excellent yields. Taking into account environmental and economical considerations, the protocol presented here has the merits of environmentally benign, simple operation, convenient workup, and good yields. © 2009 Wiley Periodicals, Inc. Heteroatom Chem 20:91–94, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20516     

One‐pot solvent and catalyst‐free synthesis of functionalized 1,8‐naphthyridines and quinolines by microwave irradiation

A series of functionalized, aryl substituted naphthyridines and quinolines has been synthesized by microwave‐assisted one‐pot two‐component synthesis under solvent‐free conditions in good yields by the reaction of a variety of aryl or heteroaryl amines and aryl vinyl ketones. A combinatorial type approach for a one‐step microwave reaction has been developed where a ring‐closing condensation is followed by a spontaneous aromatization to afford the functionalized aryl substituted 1,8‐naphthyridines and quinolines.     

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.     

One‐step synthesis of aminopyrimidines from 5‐Oxo‐4H‐benzopyrans

Novel 4‐amino‐6‐aryl‐2‐phenylpyrimidine‐5‐carbonitriles have been prepared in one step procedure from the readily available 4‐aryl‐2‐amino‐3‐cyano‐5,6,7,8‐tetrahydro‐7,7‐dimethyl‐5‐oxo‐4H‐benzopyrans. The mass spectroscopy study under EI conditions shows molecular peaks with high intensity corresponding to the loss of benzonitrile from the C2 position of the pyrimidine ring. Semiempirical (AMI and PM3) and ab initio HF/6–31G* calculations reveal a favored distorted geometry where the three rings are not in the same plane.     

One‐pot synthesis of symmetrically disubstituted 3H‐phenoxazin‐3‐ones by selective oxidative condensation with LTA

A one‐pot synthesis of some new 2,8‐disubstituted 3H‐phenoxazin‐3‐ones from 4‐substituted‐2‐aminophenols through a selective oxidative condensation by lead tetraacetate in acetic acid is described.     

One‐pot synthesis of hyperbranched glycopolymers by RAFT polymerization

Soluble hyperbranched glycopolymers were prepared by copolymerization of glycan monomers with reversible addition‐fragmentation chain transfer polymerization (RAFT) inimers in a simple one‐pot reaction. Two novel RAFT inimers, 2‐(methacryloyloxy)ethyl 4‐cyano‐4‐(phenylcarbonothioylthio)pentanoate (MAE‐CPP) and 2‐(3‐(benzylthiocarbonothioylthio)propanoyloxy)ethyl acrylate (BCP‐EA) were synthesized and used to prepare hyperbranched glycopolymers. Two types of galactose‐based saccharide monomers, 6‐O‐methacryloyl‐1,2:3,4‐di‐O‐isopropylidene‐D ‐galactopyranose (proGal‐M) and 6‐O‐(2′‐acrylamido‐2′‐methylpropanoate)‐1,2:3,4‐di‐O‐isopropylidene‐D ‐galactopyranose (proGal‐A), containing a methacrylate and an acrylamide group, respectively, were also synthesized and polymerized under the mediation of the MAE‐CPP and BCP‐EA inimers, respectively. In addition, hyperbranched poly(proGal‐M), linear poly(proGal‐A), and hyperbranched poly(proGal‐A) were generated and their polymerization kinetics were studied and compared. An unexpected difference was observed in the kinetics between the two monomers during polymerization: the relationship between polymerization rate and concentration of inimer was totally opposite in the two monomer–inimer systems. Branching analysis was conducted by using degree of branching (DB) as the measurement parameter. As expected, a higher DB occurred with increased inimer content. Furthermore, these polymers were readily deprotected by hydrolysis in trifluoroacetic acid solution resulting in water‐soluble polymers. The resulting branched glycopolymers have potential as biomimetics of polysaccharides. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012     

Solvent‐free synthesis of 2H‐pyrans: One‐pot reactions of dithiocarbamates,alkyl propiolates,and isocyanides

A novel, convenient, and an efficient approach to the synthesis of 2H‐pyrans has been reported based on the multicomponent reaction. Solvent‐free condition for the reaction of dithiocarbamates, alkyl propiolates and isocyanides lead to the formation of 2H‐pyrans in good yields. In these reactions, synthesis of 2H‐pyrans is possible based on the one‐pot reaction and without using any catalyst. The mild reaction conditions and high yields of the products exhibit the good synthetic advantage of these methods. J. Heterocyclic Chem., lpar;2011).     

One‐pot synthesis of benzimidazole‐pyrazines and their anticancer activities

The skeleton of fused benzimidazole‐pyrazine was constructed via an Ugi/deprotection/cyclization (UDC) and hydroamination cascade reaction. This four‐step reaction was carried out in a one‐pot procedure with only one‐time column chromatography purification. The representative compound 7b exhibited 67% cell growth inhibitory activity against human breast cancer cell line MDA‐MB‐453 at the concentration of 10μM.     

One‐pot synthesis of composite microspheres with core‐shell structure

One‐pot synthesis of thermoresponsive magnetic composite microspheres with a poly(N‐isopropylacrylamide) (PNIPAM) shell and a Fe₃O₄ core is demonstrated. Temperature sensitivity of PNIPAM was adopted to design the novel synthesis pathway. The as‐prepared composite microspheres have an obvious core‐shell structure with a mean size of approximately 250 nm. The Fe₃O₄ core is approximately 5 nm and the thickness of the PNIPAM shell is approximately 10 nm. The content of Fe₃O₄ in the composite microspheres can be controlled by this method. The composite microspheres experience a swelling and shrinking process in water by adjusting the temperature below and above the lower critical solution temperature (LCST) around 32 °C. These microspheres also show fine response to an external magnetic field. This work presents a platform to synthesize organic/inorganic composite microspheres in a facile and efficient approach. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2702–2708     

One‐pot double click reactions for the preparation of H‐shaped ABCDE‐type quintopolymer

We employed for the first time double click reactions: Cu(I) catalyzed azide‐alkyne 1,3‐dipolar cycloaddition and Diels–Alder (4 + 2) reactions for the preparation of H‐shaped polymer possessing pentablocks with different chemical nature (H‐shaped quintopolymer) using one‐pot technique. H‐shaped quintopolymer consists of poly(ethylene glycol) (PEG)‐poly(methylmethacrylate) (PMMA) and poly(ε‐caprolactone) (PCL)‐polystyrene (PS) blocks as side chains and poly (tert‐butylacrylate) (PtBA) as a main chain. For the preparation of H‐shaped quintopolymer, PEG‐b‐PMMA and PCL‐b‐PS copolymers with maleimide and alkyne functional groups at their centers, respectively, were synthesized and simply reacted in one‐pot with PtBA with α‐anthracene‐ω‐azide end functionalities in N,N‐dimethylformamide (DMF) using CuBr/N,N,N′,N″,N″‐pentamethyldiethylenetriamine (PMDETA) as catalyst at 120 °C for 48 h. The precursors and the target H‐shaped quintopolymer were characterized comprehensively by ¹H NMR, UV, FTIR, GPC, and triple detection GPC. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 3409–3418, 2009     

Acid chloride‐functionalized hyperbranched polyester for facile and quantitative chain‐end modification: One‐pot synthesis and structure characterization

Carboxylic acid chloride end‐functionalized all‐aromatic hyperbranched polyesters were prepared from the bulk polycondensation of the AB₂ monomer 5‐(trimethylsiloxy)isophthaloyl dichloride. The acid chloride end functionality of the hyperbranched polyester was modified in situ with methanol and yielded methyl ester ends in a one‐pot process. Chain‐end functionalization and esterification were quantitative according to both potentiometric titration and ¹H NMR analysis. The signals of ¹H and ¹³C NMR spectra of the esterified hyperbranched polyester were fully assigned from model compounds of the focal, linear, dendritic, and terminal units. The degree of branching and molecular weight averages measured by ¹H and ¹³C NMR spectroscopy and multidetector size exclusion chromatography increased systematically with increasing polymerization temperatures between 80 and 200 °C. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2855–2867, 2002     

One‐pot direct synthesis of fluorescent polyaniline‐porphyrin macrospheres from porphyrin

Porphyrins are very important chromophores as sensitizer in solar cell. Hole and electron transport layers are being used as an important layer to move the electrons and holes away from the sensitizer molecule to electrodes. In this work, a simple process has been developed for the synthesis of one layer combination of sensitizer and hole transport, that is, polyaniline‐porphyrin (PANI‐TPPS₄) system as a bulk heterojunction. Macrospheres of fluorescent PANI‐TPPS₄ materials were synthesized by one‐pot as well as two step processes directly from porphyrin for the first time. The advantage of this process is no need to isolate sulfonated porphyrin (TPPS₄), which is a difficult process. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012     

One‐pot synthesis of star‐block copolymers using double click reactions

3‐Arm star‐block copolymers, (polystyrene‐b‐poly(methyl methacrylate))₃, (PS‐b‐PMMA)₃, and (polystyrene‐b‐poly(ethylene glycol))₃, (PS‐b‐PEG)₃, are prepared using double‐click reactions: Huisgen and Diels–Alder, with a one‐pot technique. PS and PMMA blocks with α‐anthracene‐ω‐azide‐ and α‐maleimide‐end‐groups, respectively, are achieved using suitable initiators in ATRP of styrene and MMA, respectively. However, PEG obtained from a commercial source is reacted with 3‐acetyl‐N‐(2‐hydroxyethyl)‐7‐oxabicyclo[2.2.1]hept‐5‐ene‐2‐carboxamide (7) to give furan‐protected maleimide‐end‐functionalized PEG. Finally, PS/PMMA and PS/PEG blocks are linked efficiently with trialkyne functional linking agent 1,1,1‐tris[4‐(2‐propynyloxy)phenyl]‐ethane 2 in the presence of CuBr/N,N,N′,N″,N″‐pentamethyldiethylenetriamine (PMDETA) at 120 °C for 48 h to give two samples of 3‐arm star‐block copolymers. The results of the peak splitting using a Gaussian deconvolution of the obtained GPC traces for (PS‐b‐PMMA)₃ and (PS‐b‐PEG)₃ displayed that the yields of target 3‐arm star‐block copolymers were found to be 88 and 82%, respectively. © Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7091–7100, 2008     

One‐pot synthesis of polymeric nanoparticle by ring‐opening metathesis polymerization

Shell‐functionalized polymeric nanoparticle was prepared through the method of polymerization‐induced self‐assembly of block copolymers [poly(2,3‐bis(2‐bromoisobutyryloxymethyl)‐5‐norbornene)‐block‐poly(7‐oxanorborn‐5‐ene‐exo‐exo‐2,3‐dicarboxylic acid dimethyl ester), PBNBE‐b‐PONBDM] via one‐pot ring‐opening metathesis polymerization of 2,3‐bis(2‐bromoisobutyryloxymethyl)‐5‐norbornene (BNBE) and 7‐oxanorborn‐5‐ene‐exo‐exo‐2,3‐dicarboxylic acid dimethyl ester (ONBDM) in a selective solvent. The compositions and the molecular weights of the copolymers were estimated by ¹H‐NMR and gel permeation chromatography. The micelles were characterized by dynamic light scattering, transmission electron micrograph, and atomic force microscopy. The results indicated that the spherical micelles constructed with bromine‐bearing PBNBE shell and PONBDM core were stable and reproducible in toluene. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010     

Microwave‐assisted one‐pot synthesis of functionalized pyrimidines using ionic liquid

An efficient one‐pot multicomponent synthesis of 2,4‐diamino‐5‐pyrimidinecarbonitrile derivatives has been achieved in excellent yields by the condensation of aromatic aldehydes, malononitrile, and guanidine using ionic liquid under controlled microwave irradiation (100 W) at 60°C. This green approach offers a number of advantages in terms of methodology, high‐product yield, short reaction time, mild reaction conditions, and easy workup. J. Heterocyclic Chem., (2011).     

One‐pot dual size‐ and shape selective synthesis of tetrahedral Pt nanoparticles

One‐pot dual size‐ and shape‐selective synthesis of tetrahedral Pt nanoparticles is achieved using the pre‐prepared Pt nanoparticles as the ‘external seeds’, and controlling the slow diffusional growth under hydrogen reduction in the presence of PVP as the capping agent. Copyright © 2006 John Wiley & Sons, Ltd.