bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of novel chiral monoaza-15-crown-5 ethers and their molecular recognition of amino acid esters
Authors: Turgut Yilmaz , Işgın Elif Sahin , Hoşgören Halil
Published: December 2009

The chiral monoaza-15-crown-5 ethers 4 and 5 were prepared from L-phenylalaninol and L-leucinol, respectively. The molecular recognition of these chiral crown ethers for L-amino acid ethyl esters was characterised by UV-visible spectroscopy. Binding constants ( Ka), free-energy changes (–Δ Go), enthalpy changes (Δ H) and entropy change (Δ S) values were determined for hosts 4 and 5 with L-amino acid ethyl ester hydrochlorides in CHCl3.
Novel stereoselective synthesis of (E)-cinnamonitriles via Heck arylation of acrylonitrile catalysed by a silica-supported bidentate arsine palladium(0) complex
Authors: Cai Mingzhong , Tong Xiaokai , Chen Junmin , Huang Yizheng
Published: December 2009

( E)-Cinnamonitriles have been synthesised stereoselectively in high yields via Heck arylation of acrylonitrile with aryl iodides catalysed by a silica-supported bidentate arsine palladium(0) complex. This polymeric palladium(0) complex can be recovered and reused without noticeable loss of activity.
Pyrazolic tripods synthesis and cation binding properties
Authors: Malek Fouad , Ramdani Abdelkrim , Radi Smaail
Published: December 2009

The synthesis of two new bipyrazolic tripods with different functionalised arms is described. The complexing properties of these compounds towards heavy metal ions (Hg2+, Cd2+, Pb2+) and alkaline metal ions (K+, Na+, Li+) were studied by a liquid–liquid extraction process and the extracted cation percentage was determined by atomic absorption measurements.
The conformation of some N,N-disubstituted arylamines
Authors: Hanson James R. , Hitchcock Peter B.
Published: December 2009

The conformation of some N,N-disubstituted arylamines has been studied by X-ray crystallography.
Synthesis of enatiomerically enriched β-amino alcohol derivatives via chiral base mediated-asymmetric deprotonation of (benzyl methyl ether) tricarbonylchromium(0) complex and electrophilic trapping with imines
Authors: Zhao Cui-Hua , Liu Li , Chen Yong-Jun , Wang Dong
Published: December 2009

Deprotonation of (benzyl methyl ether)tricarbonylchromium(0) complex 1 by chiral base 2 followed by quenching reaction with imines 3 and subsequent decomplexation give β-amino alcohol derivatives 5 in good yields and high enantioselectivities (up to 96% e.e.).
Kinetics and mechanism of the oxidation of substituted benzyl alcohols by [bis(trifluoroacetoxy)iodo]benzene
Authors: Kansara Alpna , Sharma Pradeep K. , Banerji Kalyan K.
Published: December 2009

The oxidation of substituted benzyl alcohols by bis(trifluoroacetoxy)iodo]benzene in aqueous acetic acid solution results in the formation of the corresponding benzaldehydes. The reaction is first order with respect to each of the alcohol, TFAIB and hydrogen ions. The oxidation of [1,1-2H2]benzyl alcohol exhibited the presence of a substantial primary kinetic isotope effect, indicating the cleavage of the α-C–H bond in the rate-determining step. Increase in the amount of water, in the solvent mixture of acetic acid and water, results in a decrease of the reaction rate. The analysis of the substituent effect in terms of Charton's LDR equation yielded an excellent correlation with negative reaction constants. A mechanism involving a hydride-ion transfer in the rate-determining step has been proposed.
Fe2(SO4)3-mediated Coiodination of Alkenes with Acetic Acid: A Convenient and Regioselective Eco-friendly Preparation of β-iodoacetates
Authors: de Mattos Marcio C.S. , Sanseverino Antonio Manzolillo
Published: December 2009

The reaction of alkenes with I2 and Fe2(SO4)3 in acetic acid at room temperature produced the corresponding β-iodoacetates in 79–92% isolated yields and high regioselectivity.
A facile stereoselective synthesis of (E)-1,2-disubstituted vinylic tellurides via hydromagnesiation of alkylarylacetylenes
Authors: Cai Mingzhong , Xia Jun , Yang Jingru
Published: December 2009

Hydromagnesiation of alkylarylacetylenes 1 in diethyl ether gave ( E)-α-arylvinyl Grignard reagents 2, which reacted with aryltellurenyl iodides 3 in THF to afford stereoselectively ( E)-1,2-disubstituted vinylic tellurides 4 in good yields.
Oxidation of 1,2-bis (cyanoalkyl) hydrazines to azobisnitriles using trichloroisocyanuric acid
Authors: Mohite S.A. , Desai Uday V. , Pore D.M. , Mane R.B. , Wadgaonkar P.P.
Published: December 2009

Azobisnitriles were synthesised in excellent yields by oxidation of the corresponding 1, 2-bis (cyanoalkyl) hydrazines using trichloroisocyanuric acid in acetonitrile medium at room temperature.
Montmorillonite K-10 catalysed solvent-free synthesis of 2,3-disubstituted-4(3H)quinazolinones under microwave irradiation
Authors: Dabiri M. , Salehi P. , Mohammadi Ali A. , Baghbanzadeh M. , Kozehgiry Gh.
Published: December 2009

An efficient and rapid synthesis of 2,3-disubstituted-4(3 H)quinazolinones by condensation of 2-aminobenzamide (substituted anthraniamides) with orthoesters in the presence of K-10 clay under solvent free conditions using microwave irradiation or classical heating is described.
Studies with 3-Substituted 2-Arylhydrazono-3-Oxoaldehydes: New Routes for Synthesis of 2-Arylhydrazono-3-Oxonitriles, 4-Unsubstituted 3,5-Diacylpyrazoles and 4-Arylazophenols
Authors: Al-Saleh Balkis , El-Apasery Morsy A. , Elnagdi Mohamed Hilmy
Published: December 2009

Compounds 1a–c reacts with hydroxylamine- O-sulfonic acid or with hydroxylamine hydrochloride in aqueous acetic acid in the presence of sodium acetate to yield the 3-oxoalkanonitriles 3, which were converted into arylazoisoxazole and 1,2,4-triazine derivatives 10. The hydrazones 1a–c reacted with chloroacetone or with phenacyl bromide in refluxing ethanol and in presence of K2CO3 to yield the pyrazoles 12a–e, formed most likely via intermediately formed 11a–e. The reaction of 1a,b with acetone afforded the arylazophenols.
4-(Nitro)-diphenylammonium triflate(NDPAT) catalysed esterification of carboxylic acids with alcohols
Authors: Liu Xuan-Gan , Hu Wei-Xiao
Published: December 2009

4-(Nitro)-diphenylammonium triflate(NDPAT) efficiently catalysed the esterification between equimolar amounts of carboxylic acids and alcohols in good yield under mild reaction conditions.
Three-component solvent-free diastereoselective formation of oxo-thiazolidinylthiazoles under microwave irradiation
Authors: Siddiqui Ibadur R. , Singh Pravin K. , Singh Jaya , Singh Jagdamba
Published: December 2009

The one-pot diastereoselective cyclisation of 4,4′-bis(2″-aminothiazol-4″-yl)bibenzyl to 4,4′-bis[2″-(2″′-aryl-5″′-methyl/carboxymethyl-4″′-thiazolidinon-3″′-yl)thiazol-4″-yl]bibenzyls, in high yields (85-96%) under the influence of microwave radiation, is described.
An unusual reaction of phenacylsulfonylacetic acid methyl ester and styrylsulfonylacetic acid methyl ester with hydrazine hydrate
Authors: Padmavathi V. , Thriveni P. , Padmaja A.
Published: December 2009

The reaction of phenacylsulfonylacetic acid methyl ester and styrylsulfonylacetic acid methyl ester with hydrazine hydrate gives unusual products, 1,1-dioxo-6-phenyl-1,2,4,7-tetrahydro-1λ6-[1,4,5]thiadiazepin-3-one and 1,1-dioxo-6-phenyl-1λ6-[1,4,5]thiadiazepan-3-one instead of the expected acid hydrazide.
The oxidation of 4-alkyl and 4-aryl-1,4-dihydropyridines to pyridines with hydrogen peroxide in an ionic liquid
Authors: Panchgalle Sharad P. , Choudhary Suman M. , Chavan Subhash P. , Kalkote Uttam R.
Published: December 2009

An efficient oxidation of 4-alkyl and 4-aryl-1,4-dihydropyridines to the corresponding pyridines with hydrogen peroxide in ionic liquids at room temperature in excellent yields is described.
The inhibition of the fungus Botrytis cinerea by some sesquiterpenoid daucanes
Authors: Collado Isidro G. , Hanson James R. , Macias-Sanchez Antonio J. , Mobbs Daniel J.
Published: December 2009

Daucol 2, 5β, 9α- and 5β, 9β-dihydroxy-(8α-H)-daucane 3 and 5, have been shown to have a fungistatic action against the plant pathogen Botrytis cinerea. The diols were metabolised to 3β, 5β, 9α-trihydroxy-(8α-H)-daucane 7 and 5β, 8α-dihydroxy-(8α-H)-daucan-9-one 8 respectively. These were biologically less active and may represent detoxification products.
Study of Binuclear Complexes with two [RuII(bpy)2]2+ Moieties Coordinated by a Bridging Binucleating Ligand (L) Bearing two Bidentate Chelating Sites
Authors: Patel Daksha , Bhattacharya Pabitra K.
Published: December 2009

Three series, each of four sets, of binuclear ruthenium(II) complexes of the type [(bpy)2RuII(L) RuII(bpy)2](ClO4)22H2O; (L = binucleating ligand, bearing two 2-hydroxy-4-( n-alkoxy)benzaldimino moieties bound to (CH2)2, (CH2)3 or 1, 4-disubstitutedbenzene bridge and, bpy = 2,2′-bipyridine), have been synthesised and characterised. The complexes are diamagnetic and comparative 1H NMR spectral studies of the complexes and the ligands establish the binuclear composition of the complexes. All the complexes display four metal-to-ligand charge transfer transitions in the visible region of the electronic spectra. In acetonitrile the complexes show one reversible oxidation process in the potential range 0.57–0.60 V, due to the oxidation of the ruthenium(II) centres to ruthenium(III). The complexes are non-luminescent at room temperature and are catalytically inactive to oxygenation reactions.
Titanium(IV) Bromide Promoted Diastereoselective Reactions of Arylaldehydes with Optically Active Propiolates
Authors: Shi Min , Wang Chun-Jiang
Published: December 2009

The diastereoselective condensation reaction of arylaldehydes with optically active derivatives of propynoic acid has been examined in the presence of the Lewis acid titanium(IV) bromide (TiBr4); we have found that moderate to excellent diastereomeric excess (de) can be achieved in this TiBr4-promoted reaction.
Synthesis of Novel Derivatives of 4-Amino-3,5-Dicyanopyrazole
Authors: Gonçalves M. Sameiro T. , Oliveira-Campos Ana M.F. , Rodrigues Lígia M. , Proença M. Fernanda R.P. , Griffiths John , Maia Hernâni L.S. , Kaja Martin , Hrdina Radim
Published: December 2009

Diazotisation of substituted arylamines followed by reaction with malononitrile gave substituted arylazomalononitriles. Cyclisation of these intermediates with chloroacetonitrile and triethylamine, as base, gave the corresponding new aminodicyanopyrazoles, in 22–80% yields.
Selective Reduction of Carbon–carbon Double Bonds of Aryl Substituted Chalcones with Zn/CH3COONH4/C2H5OH/H2O
Authors: Zhou Yong-bo , Wang Yu-lu , Wang Jin-ye
Published: December 2009

In this paper, 12 aryl substituted chalcones are easily reduced to the corresponding saturated carbonyl compounds using Zn/CH3COONH4/C2H5OH/H2O under mild condition with excellent yields for the first time.
Synthesis of Novel Carboxylated Benzoxazolylcoumarins
Authors: Rodrigues Lígia M. , Luan X. H. , Oliveira Ana M.A.G. , Oliveira-Campos Ana M.F.
Published: December 2009

Six novel coumarins containing carboxylic ester or acid groups were prepared. The compounds were characterised by the usual methods. In a few cases the fluorescence data were obtained.
Oxidative Deprotection of Trimethylsilyl Ethers using Bismuth Nitrate Supported onto Montmorillonite k-10 under Microwave Irradiation in Solventless System
Authors: Heravi Majid M. , Oskooie Hossein A , Yazdanpanah Sedigheh , Mojtahedi Majid
Published: December 2009

Primary and secondary trimethylsilyl ethers are converted to their carbonyl compounds efficiently using montmorillonite k-10 supported bismuth nitrate under microwave irradiation in a solventless system.
Reductive Coupling of Benzylic and Allylic Halides with Sodium Dithionite in DMF or HMPA
Authors: Khurana Jitender M. , Bansal Geeti , Sahoo Prabhat K.
Published: December 2009

Reductive coupling of secondary benzylic halides is reported with sodium dithionite in dry DMF or HMPA at 155-160°C under N2 atmosphere. Primary benzylic and allylic halides gave the reductively coupled dimers and/or sulfones. The formation of the products is proposed by SET from sulfur dioxide radical-anion.
N,N-Dibromobenzenesulfonamide as a Reagent for Oxidative Cleavage of Oximes to Their Parent Carbonyl Compounds Under Non-Aqueous and Aprotic Conditions
Authors: Tajbakhsh Mahmood , Khazaei Ardeshir , Shabani–Mahalli Majid , Ghorbani–Vaghei Ramin
Published: December 2009

Deprotection of different oximes to their parent aldehydes and ketones in high yields has been carried out by using N,N-dibromobenzenesulfonamide(dibromoamine-b) under mild conditions.
Investigation of Spontaneous Polycondensation of N-(O, O-Ditetradecyl) Phosphorylalanine in Highly Ordered Films by Ftir Spectroscopy
Authors: Xiao Yi , Li Yan-Mei , Wang Hai-Yan , Zhao Yu-Fen , Sun Li , Zhao Bing , Zhang Xi
Published: December 2009

Spontaneous polycondensation to polypeptides on both cast films and Langmuir-Blodgett films (LB films) of N-(O, O-ditetradecyl)phosphorylalanine (DNTP-L-Ala) was studied by FTIR transmission spectroscopy.
Chloramine-T Mediated Synthesis of 1,2,4-Triazolo[4,3-a] [1,8]Naphthyridines Under Microwave Irradiation
Authors: Mogilaiah K. , Reddy G. Randheer
Published: December 2009

An effective, practical and simple approach towards the synthesis of 1,2,4-triazolo[4,3- a][1,8]naphthyridines 8 from the corresponding aryl aldehyde 3-( m-chlorophenyl)-1,8-naphthyridin-2-ylhydrazones 7 has been described, using chloramine-T in combination with microwave irradiation; the products are obtained in good yields and in a state of high purity.
Kinetics of the Alkaline Hydrolysis of 2-Thioaryl-3, 5-Dinitropyridine Derivatives in 50% v/v DMSO–water
Authors: Fathalla Magda F. , Ibrahim Mahmoud F. , Hamed Ezzat A.
Published: December 2009

The kinetics of the alkaline hydrolysis of substituted 2-thioaryl-3,5-dinitropyridine have been studied in 50% DMSO– water. The observed rate constants and the second order rate constants were calculated. The thermodynamic parameters for the unsubstituted compound reveals the activating power of the two nitro- and aza-groups.
Synthesis of Chalcones Catalysed by SOCl2/EtOH
Authors: Hu Zhiguo , Liu Jun , Dong Zhibing , Guo Lili , Wang Dong , Zeng Pingli
Published: December 2009

A novel and efficient synthesis chalcones by using SOCl2/EtOH as catalyst was presented. In the presence of thionyl chloride, the aldol condensation of acetophenone and benzaldehyde was catalysed in the anhydrous ethanol in high yields (60–95%) under mild condition.
A New Method for the Synthesis of γ-Oxobutyronitriles via Addition of Aroyl Chlorides to Acrylonitrile Promoted by Samarium Metal in DMF
Authors: Liu Yongjun , Zhang Yongmin
Published: December 2009

Without any pretreatment or activator, metallic samarium in DMF promotes the addition of aroyl chlorides to acrylonitrile to form γ-oxobutyronitriles
A Theoretical Study of Metal-Stabilised Rare Tautomers Stability: N4 Metalated Cytosine (M=Be2+, Mg2+, Ca2+, Sr2+ and Ba2+) in Gas Phase and Different Solvents
Authors: Monajjemi Majid , Ghiasi Reza , Ketabi Sepideh , Passdar Hoda , Mollaamin F.
Published: December 2009

Ab initio calculations are applied in order to explore metalation of the exocyclic amino group of cytosine by the elements of group IIA (Be, Mg, Ca, Sr and Ba).
Supramolecular Polymers of two Novel 4-Substituted-1,2,4-Triazolate Complexes: [Cd(pCltrz)2(NCS)2(H2O)2] and [Cu(4-atrz)4(Cl)0.5(H2O)0.5]·(ClO4)1.5 (pCltrz: 4-(p-chlorophenyl)-1,2,4-triazole; 4-atrz: 4-amino-1,2,4-triazole)
Authors: Yi Long , Du Jian-Yun , Liu Sheng , Wang Xiao-Xiao
Published: December 2009

The synthesis and structural characterisation of two novel complexes of 4-substituted-1,2,4-triazoles, namely [Cd(pCltrz)2(NCS)2(H2O)2] (1) and [Cu(4-atrz)4(Cl)0.5(H2O)0.5]·(ClO4)1.5(2), are described. Elemental analysis, IR spectra and X-ray crystal structure analysis were carried out to determine the compositions and crystal structures of two compounds. The cadmium atom in 1 has a distorted octahedral coordination and forms one-dimensional chains via hydrogen bonding contacts. 2 has a distorted pyramid environment at the copper atom and a unique double-layer supramolecular structure connected via hydrogen bonds.
Efficient and Chemoselective Deprotection of 1,1-Diacetates Using Fe2(SO4)3·xH2O as a Heterogeneous Catalyst
Authors: Li Lingjun , Zhang Xinying , Zhang Guisheng , Qu Guirong
Published: December 2009

Various substituted 1,1-diacetates are smoothly transformed to the corresponding aldehydes by using hydrated ferric sulfate as heterogeneous catalyst at reflux in dichloroethane. The advantages of this methodology are: high yields, good chemoselectivity, inexpensive and environmentally benign catalyst as well as short reaction time and operational simplicity.
Study of Differences in the Reactivity of Alkyl and Aryl Nitrones Derived from 4-oxo-4H-1-Benzopyran-3-Carboxaldehyde
Authors: Ghosh Tarun , Patra Ranjan , Bandyopadhyay Chandrakanta
Published: December 2009

On hydrolysis with 70% H2SO4, aliphatic nitrones 2a–d produce the corresponding carboxylic acids 4 but aromatic nitrones 2e, f give aldehyde 1. On heating under reflux in dry MeOH, 2a–d rearrange to 3a–d but aromatic nitrones 2e, f remain unchanged.
Synthesis of α, α′-bis(Substituted Benzylidene)Ketones Catalysed by a SOCl2/EtOH reagent
Authors: Hu Zhi Guo , Liu Jun , Zeng Ping Li , Dong Zhi Bing
Published: December 2009

The cross-aldol condensations of cyclopentanone, cyclohexanone and acetone with benzaldehyde or cinnamaldehyde were catalysed in the presence of SOCl2, in anhydrous ethanol to synthesise α, α'-bis(substituted benzylidene) ketones with excellent yields(92–97%).
The hydrogenolysis of N-Benzyl Groups with Magnesium and Ammonium Formate
Authors: Babu S.N. Narendra , Srinivasa G.R. , Santhosh D.C. , Gowda D. Channe
Published: December 2009

The selective deprotection of several N-Bn amino derivatives to the corresponding amines and the removal of S-Bn and O-Bn groups from the protected amino acids with ammonium formate and magnesium is reported.
Interpretation of the Kinetic Mechanism and the Structural Sensitivity of the Catalytic CO–NO Reaction
Authors: Cortés Joaquín , Araya Paulo , Betancourt Fernando , Díaz Francisco
Published: December 2009

The experimental results for the superficial reduction reaction of NO by CO over a number of different particle size rhodium catalysts supported on silica have been analysed quantitatively by the kinetic mechanism of Peden and Permana. The increased activity with increasing particle size can be interpreted by considering that the sites located near the edges of supported particles would have a lower dissociation capacity.
MoO2(acac)2 Catalysed Oxidative Deprotection of Oximes
Authors: De Surya Kanta
Published: December 2009

Oximes undergo facile deprotection in acetone in the presence of a catalytic amount of MoO2(acac)2 and hydrogen peroxide.
Organic Reactions in Ionic Liquids: A Novel Method for the Synthesis of 2-Arylthiobenzothiazoles by the S-Arylation of Benzolthiazole-2-Thiol with Diaryliodonium Salts
Authors: Wang Feng-Yan , Chen Zhen-Chu , Zheng Qin-Guo
Published: December 2009

2-Arylthiobenzothiazoles were readily prepared in good yields by the S-arylation of benzothiazole-2-thiol with diaryliodonium salts at room-temperature in the ionic liquid, 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim]BF4). The ionic liquid can be recycled and reused.
Topological analysis and quantum mechanical structure of Hn+ clusters II. H5+ and H7+
Authors: Sadjadi Abdolreza , Abdzadeh Maryam
Published: December 2009

Full typologocal and chemical features of H5+ and H7+ have been calculated at RHF/6-311G(3P) using AIM theory. The results have been compared with previous work on H3+.
Synthesis of 4H,5H-pyrano[3,2-c][1]benzopyran-5-ones in aqueous media
Authors: Wang Jing , Shi Daqing , Zhuang Qiya , Wang Xiangshan , Hu Hongwen
Published: December 2009

The reaction of substituted cinnamonitriles with 4-hydroxycoumarin in water in the presence of triethylbenzyl-ammonium chloride affords 2-amino-4-aryl-4H,5H-pyrano [3,2-c] [1]benzopyran-5-one derivatives.
Reduction of acid chlorides using dichloro bis[(1,4-diaza bicyclo [2.2.2] octane) bis(tetrahydroborato)] zirconium (IV)
Authors: Alinezhad Heshmatollah , Tajbakhsh Mahmood , Salehian Fatemeh
Published: December 2009

Aliphatic and aromatic acid chlorides were efficiently reduced to give the corresponding alcohols when treated with [Zr(BH4)2Cl2(dabco)2], (ZrBDC).
An efficient and practical synthesis of β-hydroxyl ketones catalysed by trisodium phosphate under ultrasound
Authors: Li Ji-Tai , Xu Wen-Zhi , Chao Xi , Li Tong-Shuang
Published: December 2009

In the presence of trisodium phosphate, cross-aldol reactions of reactive aldehydes with substituted acetophenone in CH3OH-water mixed solvent afford β-hydroxyl ketones in good to excellent yields under ultrasound irradiation.
One-pot synthesis of 2-amino-4-aryl-5-oxo-5,6,7,8-tetrahydro-4H-1-benzopyran-3-carbonitriles in aqueous media
Authors: Shi Daqing , Mou Jie , Zhuang Qiya , Wang Xiangshan
Published: December 2009

The reaction of aromatic aldehyde, malononitrile and 1,3-cyclohexanediones in water in the presence of triethylbenzyl-ammonium chloride (TEBA) provides an efficient access to 3-cyano-substituted 2-amino-4-aryl-4,6,7,8-tetrahydro-5H-1-benzopyran-5-ones.
Stereoselective Synthesis of α-Alkyl-α-Hydroxylphenylacetic Acid Part (I): Asymmetric Alkylation of (S)-Mandelic Acid
Authors: Han Xiang-Yu , Liu He , Liu Chun-He , Wu Bo , Zhong Bo-Hua , Liu Ke-Liang
Published: December 2009

An effective asymmetric synthesis of α-alkyl-α-hydroxyl phenyl acetic acid using benzaldehyde as steric hindrance agent has been accomplished by utilising the readily available and inexpensive chiral starting material, (S)-mandelic acid. The ee was determined by 1H NMR with Eu(hfc)3 as shift reagent.
The Westphalen rearrangement of 5α, 6α-epoxy-3β-methanesulfonyloxy-androstan-17-one
Authors: Knights Steve G. , Hanson James R.
Published: December 2009

5α,6α-Epoxy-3β-methanesulfonyloxyandrostan-17-one undergoes a Westphalen backbone rearrangement rather than an aromatisation in acetic acid: acetic anhydride containing sulfuric acid catalyst, suggesting that under these conditions the formation of a 5α-sulfate from the epoxide and its ionisation takes precedence over the elimination of the 3β-methanesulfonate.
Steric acceleration of activated ene reactions
Authors: Sammes Peter G. , Smith Graham , Ward Robert W.
Published: December 2009

Steric buttressing has been used to effect ene reactions involving conjugated enoic esters under relatively mild conditions and with improved control of observed stereoselectivities.
Synthesis of clusters containing the OsCoMoS core
Authors: Hu Bin , Zhao Pei-Qing , Zhao Quan-Yi , Xia Chun-Gu , Yin Yuan-Qi , Sun Jie
Published: December 2009

Several new chiral tetrahedral clusters containing the OsCoMoS core were synthesised by the thermal reaction of the precursor [(μ 3-S)OsCo2(CO)9] with the functionally-substituted metal exchange reagents [Mo(CO)3(C5H4)R][(R=CHO, C(O)CH3, C(O)C6H4-1,4-CO2Me)]. The structure of cluster [(μ 3-S)OsCoW(CO)8C5H4C(O)CH3] was established by X-ray single crystal diffraction.
Michael addition of nitromethane to isopropylidene 5-alkylidenemalonates
Authors: Li Jing-Hua , Li Zu-Guang , Chen Qing-Guang
Published: December 2009

The nitroethyl derivatives of isopropylidene malonate 2, which were unknown, are synthesised by way of Michael addition of nitromethane to isopropylidene 5-alkylidenemalonates, among them 2,2-dimethyl-5-[1-(nitromethyl)cyclohexyl]-1, 3-dioxane-4,6-dione 2a, which can be used as a new intermediate for synthesising Gabapentin.
The preparation of α,α‘-bis(substituted benzylidene) cycloalkanones
Authors: Hai-Ying Li , Wen-Zhi Yang , Jiang-Bin Yang , shun-sheng Huang , Ji-Tai Li
Published: December 2009

Claisen–Schmidt condensation of cyclopentanone or cyclohexanone with aromatic aldehydes catalysed by potassium fluoride supported on molecular sieve or potassium fluoride supported on alumina results 2,5-bis(substituted benzylidene) cyclopentanones or 2,6-bis(substituted benzylidene) cyclohexanones in 56–95% and 60–98% yields respectively in refluxed methanol.
Indium tribromide/[bmim]PF6: A novel and recyclable catalytic system for the deprotection of 1,1-diacetates
Authors: Zhang Zhan-Hui
Published: December 2009

A mild and highly efficient method has been developed for the deprotection of 1,1-diacetates using a catalytic amount of indium tribromide immobilised in 1-butyl-3-methylimidazolium hexafluorophosphate as an ionic liquid. This affords the corresponding the parent aldehydes in excellent yields. The recovered ionic liquid containing catalyst has been recycled in three subsequent runs.
Oxidative monobromination of electron-rich arenes by conc. H2SO4 / alkali metal bromides
Authors: Myint Yi Yi , Pasha M. A.
Published: December 2009

The reaction of electron-rich arenes with alkali metal bromides such as sodium and potassium bromides in the presence of conc. H2SO4 to give p-bromoarenes is reported. The reaction is possible in the absence of any specialised oxidising agents and the yields are high.
New mixed ligand complexes of dicyclopentadienyl titanium(IV) derived from sterically congested heterocyclic β-diketones and N-protected amino acids
Authors: Verma Shashi , Joshi Anurag , Jain Asha , Saxena Sanjiv
Published: December 2009

New mixed ligand monomeric complexes of dicyclopentadienyl titanium(IV) of general formula, [Formula: see text] have been synthesised by the reaction of titanocenedichloride with sterically congested heterocyclic β-diketones and N-protected amino acids in the presence of triethylamine in refluxing THF. Plausible structures for these mixed ligand complexes have been suggested
The reactivity–selectivity principle in the oxidation of aryl methyl sulfides with sodium hypochlorite catalysed by (salen)MnIII complexes
Authors: Chellamani Arunachalam , Harikengaram Sivalingam
Published: December 2009

The kinetics of oxygen atom transfer from four oxo(salen)manganese(V) complexes to various para-substituted phenyl methyl sulfides have been studied spectrophotometrically in 90% acetonitrile-10% water(v/v) at 20oC. Electron-releasing substituents in sulfides and electron-withdrawing substituents in oxo(salen)manganese(V) complexes enhance the rate of oxidation. Correlation analyses establish that there is an inverse relationship between reactivity and selectivity in both the sulfide and the complex series. Mathematical treatment of the results shows the operation of a valid reactivity-selectivity principle in this redox system.
A mild and efficient deprotection of geminal diacetates catalysed by FeCl3·6H2O in ionic liquid
Authors: Niu Hongying , Zhang Xinying , Guo Haiming , Wang Jianji
Published: December 2009

The selective deprotection of geminal diacetates promoted by FeCl3·6H2O in the ionic liquid, [bmim][BF4], can be efficiently achieved in good yield. The process is carried out under mild conditions, and the ionic liquid and the catalyst can be recycled easily.
One-pot synthesis of new macroheterocyclic phosphoranes
Authors: Babu Yaramapa Hari , Reddy Cirandur Suresh , Reddy Chichili Devendranath , Raju Chamarthi Naga
Published: December 2009

Synthesis of new macroheterocyclic phosphoranes (2a–j) was achieved by one-pot reaction of equimolar quantities of N,N-bis-(5-t-butyl-2-hydroxy-benzyl) cyclohexylamine (1), POCl3 and various substituted phenols in the presence of NEt3 in toluene at room temperature with stirring for 1 to 3 days under nitrogen. Their chemical structures were established by analytical and spectroscopic data.
A facile and practical method for the preparation of thioacetates from alkyl halides and sodium thioacetate catalysed by PEG400
Authors: Cao Yu-Qing , Du Yun-Fei , Chen Bao-Hua , Dai Zhi
Published: December 2009

Thioacetates are conveniently prepared in high yields under mild conditions by the reaction of alkyl halides and sodium thioacetate, prepared in situ from thioacetic acid and sodium carbonate, catalysed by PEG400 at room temperature.
Reductive fission of azoarenes to aminoarenes by aluminium/hydrazine hydrate
Authors: Pasha M.A. , Nanjundaswamy H.M.
Published: December 2009

Various azoarenes undergo reductive fission with hydrazine hydrate in refluxing ethanol to give easily isolable aminoarene(s) using aluminium powder. The reaction is fast and cost effective: yields are excellent ranging from 85-95%; substituents like –OH, –OCH3, –COOH, –Cl, –Br are unaffected. The method affords a simple and convenient route to the preparation of substituted aminoarenes.
6-(α-Hydroxy-α-aryl/naphthyl)methyl-3,4-dihydro-2,5-benzodiazocin-1(2H)-ones and diphenylmethanes from C-2 arylated 1,3-indanediones
Authors: Kundu Sandip Kumar , Das Suven , Pramanik Animesh
Published: December 2009

Stirring 2-hydroxy-2-aryl-1,3-indanediones in ethylenediamine at room temperature for 1-2 h produces 6-(α-hydroxy-α-aryl/naphthyl)methyl-3,4-dihydro-2,5-benzodiazocin-1(2H)-ones in high yields. Under similar reaction conditions 2,2-diaryl-1,3-indanediones furnish diphenylmethanes.
InCl3·4H2O/TMSCl-Catalysed Aldol Reaction of Aromatic Aldehydes with Cycloalkanones in Ionic Liquid Medium
Authors: Hu Xueyuan , Fan Xuesen , Zhang Xinying , Wang Jianji
Published: December 2009

An efficient and practical preparation of α,α′-bis(substituted benzylidene) cycloalkanone derivatives from cycloalkanones and aromatic aldehydes promoted by InCl3•4H2O/TMSCl in ionic liquid ([bmim][BF4]) is described.
Base-Catalysed Hydrolysis and Reactivity-Spectra Correlations of (Z)-4-Benzylidene-2-(Substituted Phenyl)Oxazol-5(4H)-ones
Authors: Palcut Marián , Benko Ján , Müller Norbert , Hritzová Ol'ga , Vollárová Ol'ga , Melikian Gaugik S.
Published: December 2009

Rate coefficients have been measured for the base-catalysed hydrolysis of a series of ( Z)-4-benzylidene-2-(substituted phenyl)-4 H-oxazol-5-ones in 70% v/v aqueous dioxan at various temperatures. The enthalpies and entropies of activation, and a Hammett reaction constant for the reaction, have been evaluated. The 1H and 13C NMR chemical shifts were assigned, as well as the IR carbonyl stretching frequencies in chloroform, after deconvolution and band separation. Successful correlations between the carbonyl stretching wavenumbers and the 13C NMR chemical shifts and the rates of the alkaline hydrolysis were found.
First Total Synthesis of Two Resveratrol Derivatives
Authors: Su Ying , Ma Junying , Peng Xuanjia , She Xuegong , Pan Xinfu , Gao Jinming
Published: December 2009

The total synthesis of two resveratrol derivatives with an isobutyryl substituent is reported for the first time.
The Influence of para Substituents on the Rotation of Aromatic Nitro Groups
Authors: Hanson James R. , Hitchcock Peter B.
Published: December 2009

The steric effect of adjacent methyl and methoxyl groups and the electronic effect of para substituents on the rotation of the plane of an aromatic nitro group relative to the plane of the aromatic ring has been investigated by X-ray crystallography. An electron-donating substituent in the para position decreases the rotation whilst an electron-withdrawing substituent increases the rotation of the plane of the nitro group relative to the aromatic ring.
A Facile Synthesis of 2-Stannyl-1,3-Enynes via Palladium Catalysed Coupling Reactions
Authors: Cai Mingzhong , Li Haigen
Published: December 2009

α-Iodoethenylstannanes undergo a direct coupling reaction with terminal alkynes in the presence of 5 mol% of tetrakis(triphenylphosphine)palladium(0) and 10 mol% of CuI in piperidine at room temperature to afford 2-stannyl-1,3-enynes in good yields.
One-Pot Three-Step Synthesis of 3-Aryl-2-Benzoylimino-4-Thiazolidinones in the Ionic Liquid [bmim+][PF6–]
Authors: Peng Yanqing , Song Gonghua , Huang Feifei
Published: December 2009

3-Aryl-2-acylimino-4-thiazolidinones are efficiently formed in 1- n-butyl-3-methylimidazolium hexafluorophosphate [bmim][PF6] as solvent in a one-pot three-step procedure. The ionic solvent could be recovered and recycled four times with no diminution in yields.
Synthesis and X-ray Crystal Structure of Ethyl (5β-Cholan-24-Oic Acid Ethyl Ester) −3α-yl Oxalate
Authors: Cox Philip J. , Nahar Lutfun , Turner Alan B.
Published: December 2009

An unexpected product, ethyl (5β-cholan-24-oic acid ethyl ester)-3α-yl oxalate, has been obtained during dimer formation studies from lithocholic acid and its molecular and crystal structure has been determined.
Asymmetric Syntheses of Both Enantiomers of Amphetamine Hydrochloride via Bakers’ Yeast Reduction of Phenylacetone
Authors: Shi Xiao-Xin , Yao Jian-Zhong , Kang Li , Shen Chun-Li , Yi Fei
Published: December 2009

Both enantiomers of amphetamine hydrochloride were stereospecifically synthesised based on bakers’ yeast reduction of phenylacetone. A simple and efficient method for the chiral inversion of (S)-1-phenyl-2-propanol 3 to (R)-1-phenyl-2-propanol 8 has been discussed.
Preparation of Chloroformates Using Bis(Trichloromethyl)Carbonate
Authors: Shi Haibo , Hu Weixiao , Sun Yaquan
Published: December 2009

The synthesis of eight chloroformates using bis(trichloromethyl)carbonate(BTC) is reported. It has been found that the yields by this BTC method are improved over the earlier phosgene method, and sodium hydroxide is better than pyridine as catalyst for the preparation of phenyl chloroformate.
The Sulfonation of Safrole with Trimethylsilylchlorosulfonate as Sulfonating Agent
Authors: Petit Philippe , Bourgeois Paul , Grignon-Dubois Micheline
Published: December 2009

The sulfonation of naturally occurring safrole with trimethylsilylchlorosulfonate yielded three new sulfonated products, two sultones and a sulfonic acid the structures of which are discussed.
Addition of Dibromocarbene to Cyclobutene: Characterisation and Mechanism of Formation of the Products
Authors: Algi Fatih , Hökelek Tuncer , Balci Metin
Published: December 2009

Cyclobutene reacted with dibromocarbene in solution to give 1,5-dibromocyclopent-1-ene (9), 1,2,6, 6-tetrabromobicyclo[3.1.0]hexane (10), and 1,2,3,6-tetrabromocyclohex-1-ene (11), in a ratio of 1:4:8, respectively. Compounds 10 and 11 were found to be formed from a second carbene addition and rearrangement under the given reaction conditions.
A stereochemical investigation of the nucleophilic addition of methyl ethyl ketone to (E)-alkyloxindolylideneacetates
Authors: El-Samahy Fatma A.
Published: December 2009

The reaction of (E)-(2-oxo-1,2-dihydroindol-3-ylidene)acetic acid esters (1) with methyl ethyl ketone in the presence of morpholine as a catalyst gave 4-oxo-2-(2-oxo-2,3-dihydro-1H-indole-3-yl)hexanoic acid esters, a diastereomeric mixture of two isomers (2A and 2B). Using aluminium oxide as a catalyst for the above reaction led to the formation of 4-oxo-3-methyl-2-(2-oxo-2,3-dihydro–1H-indole-3-yl)-pentanoic acid esters as a mixture of three isomers 3A, 3B and 3C, which upon methylation with methyl iodide in acetone and in the presence of anhydrous potassium carbonate yield the corresponding methylated products. The structural assignments of the new compounds are based on their chemical and spectroscopic properties. The stereochemical structures of 5aA, 5bB and 5aC are identified by X-ray analysis.
Lewis acid promoted Kharasch-type additions of 3-bromoacetyl-2-oxazolidinone to cycloalkenes
Authors: Kavrakova Ivanka K. , Mills Jeremy H.
Published: December 2009

Radical ytterbium trifluoromethanesulfonate promoted atom-transfer additions of 3–bromoacetyl-2-oxazolidinone to several cycloalkenes proceeded smoothly to give functionalised cycloalkane derivatives in good yields and stereoselectivities. All products were easily and cleanly debrominated with tri(trimethylsilyl)silane to the corresponding stable cycloalkylacetic acid derivatives.
The behaviour of 4-alkoxy methylene-2-phenyl-4H-oxazol-5-one and 4-dimethyl amino methylene-2-phenyl-4H-oxazol-5-one toward nitrogen nucleophiles under microwave heating
Authors: Anwar Hany Fakhry , Metwally Nadia Hanafy , Gaber Hatem , Elnagdi Mohamed Hilmy
Published: December 2009

The reactivity of 4-ethoxymethylene-2-phenyloxazol-5(4H)-one and 4-dimethylamino methylene-2-phenyloxazol-5(4H)-one toward amines and active methylene reagents under microwave heating is reported. A new 3-aroylamino-4-pyridone synthesis is described.
Kinetics and Mechanism of Oxidation of L-Proline by Heptavalent Manganese: A Free Radical Intervention and Decarboxylation
Authors: Mahesh R.T. , Bellakki M.B. , Nandibewoor S.T.
Published: December 2009

The kinetics of oxidation of L-proline by permanganate in alkaline medium was studied spectrophotometrically. The reaction is first order with respect to[MnO4-] and is an apparent less than unit order, each in [L-proline] and [alkali] under the experimental conditions. The reaction rate increases with increase in ionic strength and decrease in solvent polarity of the medium. Addition of reaction products has no effect on the reaction rate. A mechanism involving the formation of a complex between the oxidant and substrate has been proposed. The reaction constants involved in the mechanism were evaluated. There is a good agreement between the observed and calculated rate constants under varying experimental conditions. The activation parameters with respect to the slow step of the proposed reaction scheme were evaluated and discussed.
Samarium diiodide mediated regeneration of 1,2-benzene diamine and preparation of benzimidazolin-2-ones from 2,1,3-benzothiadiazoles
Authors: Fan Xuesen , Zhang Xinying , Zhang Yongmin
Published: December 2009

On treatment with SmI2 in THF and in the presence of methanol, 2,1,3-benzothiadiazoles underwent reductive N–S bond cleavage leading to 1,2-benzenediamines in high yields. Without methanol but in the presence of triphosgene, benzimidazolin-2-ones were obtained in moderate yields under mild conditions.
Some Reactions of 3-Chloroisoindolium Salts with Nucleophiles: Access to Isoindole Derivatives and Ellipticine Analogues as Potential Antiviral Agents
Authors: Hamed Atef A.
Published: December 2009

3-Chloro-2-substituted-1-oxoisoindolium hexachloroantimonate (1) reacted with water, ethanol and dimethyl-cyanamide to give the corresponding phthalimide derivatives 2, 3 and 4 respectively. Reaction of 1a with nitriles afforded the intermediate 2-azoniaallene salts 5 which underwent cyclisation reaction upon heating to furnish the ellipticine analogues 6. The biological activities of 6a–e against HIV-1 and HBV viruses were determined.
Fast microwave-assisted oxidation of 1,4-dihydropyridines with FeCl3.SiO2
Authors: Hosseini Abolfazl , Halvagar Mohammad Reza , Khalilzadeh Mohammad Ali , Alaee Ehsan , Tajbakhsh Mahmood
Published: December 2009

Pyridine derivatives are easily obtained in high yields by microwave-promoted rapid oxidation of the corresponding 1,4-dihydropyridines with ferric chloride hexahydrate and silica gel under solvent-free conditions.
An Efficient and Mild Direct Oxidative Methyl Esterification of Aromatic Aldehydes Using NaBr and Diacetoxyiodobenzene
Authors: Karade N.N. , Shirodkar S.G. , Dhoot B.M. , Waghmare P. B.
Published: December 2009

Diacetoxyiodobenzene combined with NaBr was found to be an efficient, mild and practical reagent for the oxidative methyl esterification of aldehydes.
Generation and Utilisation of P-cyclic α-methoxycarbonyl-methylenephosphoranes
Authors: Keglevich György , Forintos Henrietta , Ujvári Anikó , Ludányi Krisztina , Bitter István , Töke László
Published: December 2009

Phosphonium salts 3 obtained by the quaternisation of 1-aryl-2,5-dihydro-1H-phospholes 2 with methyl bromoacetate are suitable precursors of the corresponding heterocyclic phosphoranes 5. They were generated in situ using DBU at ambient temperature. The phosphoranes (5) were used in Wittig reaction with benzaldehydes and in acylation with methyl (chloroformyl)formate to afford in the latter case, heterocyclic α,β-bis(methoxycarbonyl)-β-oxophosphoranes (7).
3-Carboxypyridinium Trichloroacetatochromate (CPTCAC): As a Mild and Effective New Reagent for the Thiols to Disulfides
Authors: Aydin Fatma , Ozen Recep
Published: December 2009

A new chromium(VI) reagent, 3-carboxypyridinium trichloroacetatochromate (CPTCAC) was prepared by reacting 3-carboxypyridine (nicotinic acid) and trichloroacetic acid with CrO3 in water. This oxidising agent oxidised the thiols to disulfides selectivily and in very high yields.
Synthesis of New Thieno- and Pyrazolo- pyridazine Derivatives
Authors: Yassin Fathy A.
Published: December 2009

5,6-Di(pyridin-2-yl)-3-thioxo-2,3-dihydropyridazine-4-carbonitrile 2 has been reacted with ahalocompounds, such as chloroacetone, chloroacetamide, ethyl chloroacetate and chloroacetic acid gave the corresponding 2-S-alkylated pyridazine derivatives 3, 6, 10 and 13 which have been cyclised to give the corresponding thienopyridazine derivatives 4, 7, 11, and 14 respectively. Reaction of 15 with hydrazine hydrate gave the corresponding pyrazolopyridazine 16.
Microwave Irradiation for Enhancing the Regioselective Synthesis of 6H-indolo[2,3-b]quinoxalines
Authors: Ashry El Sayed H. El , Ramadan El Sayed , Hamid Hamida Abdel , Hagar Mohamed
Published: December 2009

Microwave irradiation (MWI) promotes the regioselective synthesis of 6H-indolo[2,3-b] quin oxaline (5) by condensation of isatin (1) with o-phenylenediamine. Ethyl indolo [2,3-b] quinoxaline-6-acetate (8) was prepared via the carbethoxymethylation of 5, or from the reaction of N-(ethoxycarbonylmethyl)isatin (6) with o-phenylenediamine under MWI. The reaction of 8 with hydrazine hydrate afforded the hydrazide 9, whose condensation with aromatic aldehydes and monosaccharides gave the hydrazones 10a–d.
Microwave Mediated Fast Synthesis of Diaminoglyoxime and 3,4-diaminofurazan: Key Synthons for the Synthesis of High Energy Density Materials
Authors: Kusurkar Radhika S , Goswami Shailesh K. , Talawar Mahadev B. , Gore Girish M. , Asthana Shri N.
Published: December 2009

This paper reports the first microwave-assisted synthesis of diaminoglyoxime (DAG) and diaminofurazan (DAF). The synthesis involved the vicarious nucleophilic substitution of H of glyoxime using hydroxylamine hydrochloride under microwave irradiation for 2 to 3 min to obtain DAG, which on further irradiation in alkali solution for 20 min yielded DAF. Conversion of glyoxime into DAF was also achieved in a one pot sequence in good overall yield using microwave irradiation.
Solid State Oxidation of Phenols to Quinones with Ammonium Persulfate/Wet SiO2
Authors: Hashemi Mohammed M. , Karimi-Jaberi Zahed , Eftekhari-Sis Bagher
Published: December 2009

A solid state method for the oxidation of phenols to quinones is described using ammonium persulfate/wet silica gel as oxidant
Efficient T-butylation of Phenol using the Wells–Dawson-type Molybdovanadophosphoric Heteropolyacid, H7P2Mo17VO62, as Catalyst
Authors: Li Guixian , Wang Bo , Wang Jianming , Yan Liang , Suo Jishuan
Published: December 2009

Wells–Dawson heteropolyacid H7P2Mo17VO62 proved to be an efficient catalyst for the alkylation of phenol with t-butyl alcohol. Under optimized conditions, 80 °C and 4 h, H7P2Mo17VO62 loads as low as 0.15 mol % can be used leading to high phenol conversion. The main product, 2, 4-di-t-butylphenol, could be obtained in moderate selectivity.
A Novel Stereospecific Aminocyclopropanation via the Dethiolation of Thioamides Promoted by the Samarium/Samarium Diiodide Mixed Reagent
Authors: Zhu Weimin , Qian Weixing , Zhang Yongmin
Published: December 2009

The stereospecific aminocyclopropanation of styrene via the dethiolation of N,N-disubstituted aromatic thioamides promoted by the samarium/samarium diiodide mixed reagent has been successfully performed.
Synthesis, Crystal Structure of 7α-[(S)-1-hydroxy-1-(2-thienyl)ethyl]-6, 14-endoethanotetrahydrothebaine
Authors: Liu Chun-he , Liu He , Han Xiang-yu , Wu Bo , Zhang Xiao-Bo , Zhong Bo-hua
Published: December 2009

7α-[(S)-2-Hydroxy-2-(2-thienyl)ethyl]-6,14-endoethanotetrahydrothebaine was synthesised and studied by 1H NMR and MS spectroscopy, its crystal structure was determined by X-ray diffraction.
The General Dienol: Benzene Rearrangement of Ring a of the Steroids
Authors: Hanson James R.
Published: December 2009

The dienol: benzene type of rearrangement of steroids, to form compounds with an aromatic ring A, occurs under acid-catalysed conditions with a wide range of substrates containing two double bond equivalents and a carbonium ion source on rings A and B.
Ruthenium Catalysed Imidation of Aldehydes Using PhI=NTs as Imido Transfer Reagent
Authors: Sharma Vishal B. , Jain Suman L. , Sain Bir
Published: December 2009

The [N-(p-tolylsulfonyl)imino] phenyliodinane (PhI=NTs) was found to be an efficient reagent for imidation of variety of aldehydes using [RuCl2(PPh3)3] as catalyst in the presence of triphenylphosphine.
Microwave Promoted Solvent-free One-pot Synthesis of N,N′-disubstituted Urea Derivatives
Authors: Jadhav Vinod H. , Deshpande Shubhada S. , Borate Hanumant B. , Wakharkar Radhika D.
Published: December 2009

An efficient one-pot synthesis of N,N′-disubstituted urea derivatives from substituted anilines, ethyl chloroformate and methyl anthranilate or methyl 3-amino-2-butenoate under microwave irradiation is reported.
One-pot Synthesis of 14H-dibenzo[a,j]xanthene and its 14-substituted Derivatives
Authors: Khoramabadi-zad Ahmad , Akbari Safar-Ali , Shiri Azam , Veisi Hojat
Published: December 2009

Preparation methods of the titled compounds are mentioned and an easy, environment friendly, common and one-pot synthesis of these compounds is described.
A Simple and Efficient Method for Synthesis of Carboxymethylated Polyethyleneglycol
Authors: Li Xing-Qi , Meng Fan-Tao , Ma Guang-Hui , Su Zhi-Guo
Published: December 2009

A simple and efficient method for the synthesis of carboxymethylated polyethylene glycol (CM-PEG) by the oxidation of the corresponding monomethoxy polyethylene glycol (mPEG) with catalytic amounts of TEMPO and hypobromide as a regenerating oxidant and water as solvent was developed.
Synthesis of New Pyrazolenines and Cyclopropenyl Alcohols Directly from Propargyl Alcohols
Authors: Hamdi Naceur , Dixneuf Pierre Henry , Arfaoui Youssef , Haloui Ezzeddine
Published: December 2009

The 1,3-dipolar cycloaddition of 2-diazopropane 1 to propargylic alcohols is regioselective and leads to 3H-pyrazoles 3 in good yield. The surprising formation of the tetrasubstitued pyrazolenine 4c from HC=CCH2OH and 1 can be explained via the 1,3-dipolar cycloadduct intermediate followed by a second cycloaddition of 1 to the C=C double bond and loss of dinitrogen. The photolysis of the antibacterial pyrazolenines 3 and 4 selectively gives α and β dimethylcyclopropenyl alcohols 5 and 6.
Synthesis and antitumor activity of N,N′-Bis(substitutedphenyl)-3, 6-dialkyl-1, 4-dihydro-s- tetrazine-1,4-dicarboxamide
Authors: Hu Weixiao , Shi Haibo , Yuan Qing , Sun Yaquan
Published: December 2009

Eleven compounds of N,N′-Bis(substitutedphenyl)-3,6-dialkyl-1,4-dihydro-s-tetrazine-1, 4-dicarboxamide were synthesised via reaction of 3,6-dialkyl-1,6-dihydro-s-tetrazine and substitutedphenyl isocyanate with yield from 24% to 86%. The antitumor activity of these compounds against P-388 and A-549 in vitro was tested. The results show that nine compounds of them showed marked antitumor activity against P-388 and seven compounds possess high antitumor activity against A-549. The IC50 of compound 3b for P-388, Bel-7402, MCF-7 and A-549 are 0.6μM, 0.6μM, 0.5 μM and 0.7μM, respectively. The substitute groups at 3, 6-position in tetrazine rings and in phenyl rings have clearly effected on their antitumor activity.
Synthesis and characterisation of a hexanuclear copper (I) cluster coordination compound
Authors: Su Bi-Quan , Xian Liang , Zhang Bin , Song Hai-Bin
Published: December 2009

A novel hexanuclear copper (I) cluster coordination compound has been synthesised by the reaction of N-ethoxy-carbonyl-N'-o-chlorophenylthiourea with cupric chloride in ethanol solution.
Synthesis of pyrazolino- and thiopyrimido- fused carbazoles from 2-ethylidene-3,4-dihydrocarbazol-1(2H)-ones
Authors: Danish Isravel Antony , Prasad Karnam Jayarampillai Rajendra
Published: December 2009

Annelated carbazoles namely, 3-methyl-1,2,3,3a,4,5,5a,10,10a,10b-decahydropyrazolino[4,5-a]carbazoles, 4a–e and 4-methyl-1,3,4,5,6,11-hexahydropyrimido[4,5-a]carbazole-2-thiones 5a–e were synthesised in excellent yields from 2-ethylidene-3,4-dihydrocarbazol-1(2H)-ones 2a–e, derived from the easily accessible 3,4-dihydrocarbazol-1(2H)-ones 1a–e.