Iranian chemical communication

Organic chemistry

Synthesis of neopentyl glycol and ethylene glycol esters by fatty acids in the presence of acidic ion exchange resin catalyst

Hadi Jabbari; Jabbar Khalafy; Peyman Najafi Moghadam

Volume 3, Issue 3, pp. 180-282,Serial No. 8 , July 2015, , Pages 244-253

Abstract

  A most effective and less energy demanding method of producing fatty esters, diol esters, by esterifying fatty acids, with neopentyl and ethylenglycol alcohols in the presence of an acidic ion exchange resin catalyst(polyestyrendivinylbenzensulfated) was investigated at elevated temperature. In this ...  Read More A most effective and less energy demanding method of producing fatty esters, diol esters, by esterifying fatty acids, with neopentyl and ethylenglycol alcohols in the presence of an acidic ion exchange resin catalyst(polyestyrendivinylbenzensulfated) was investigated at elevated temperature. In this process an azeotroping agent, toluene, was used to facilitate continuous removal of water by distillation, formed as a by-product during the esterification reaction.The esterification reaction is completed within 4-5 hours and neopentyl and ethylenglycol esters produced with properties of lubricity and biodegradability One of the most important modifications of the carboxyl group of the fatty acid chain is the esterification of the fatty acids obtained by cleavage of such esters. Those processes are performed on large scale. Esterification reactions of neopentylpolyols are normally catalysed with acidic or basic catalysts.Typical homogeneous catalysts are p-toluene sulphonic acid, phosphoric acid, sulphuric acid, sodium hydroxide, sodium ethoxide and sodium methoxide[1-5]. In some cases, heterogeneous catalysts such as Sn-oxalate or cation exchange resins are used. Enzyme catalysed reactions are also known

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Organic chemistry

Denture base polymers, poly methyl methacrylate improved using free radical copolymerization

Abdoulhossien Massoudi; Azam Louie; Omid Louie

Volume 3, Issue 3, pp. 180-282,Serial No. 8 , July 2015, , Pages 276-282

Abstract

  Poly methyl methacrylate (PMMA) is the most common material used in Prosthodontics. Several studies indicate a breakdown of the number of very high resin bases after 2 to 3 years to avoid breaking bass and several attempts have been made, such as altering the chemical structure of resin by adding causes ...  Read More Poly methyl methacrylate (PMMA) is the most common material used in Prosthodontics. Several studies indicate a breakdown of the number of very high resin bases after 2 to 3 years to avoid breaking bass and several attempts have been made, such as altering the chemical structure of resin by adding causes cross linking or copolymerization. The innovative method for improving the physical properties of the prosthesis and increase its strength, a copolymer of styrene - methyl methacrylate was proposed. Tensile strength increased with the increase of styrene with methyl methacrylate in an amount determined to be the most resistant. Polystyrene and poly methyl methacrylate and copolymers characterized by FTIR, CNMR and Tg and tensile strength were measured according to ISO1567 standard.

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Organic chemistry

Microwave assisted green synthesis of α, ά- bis (substituted- benzylidene) alkanones

Mohammad Ali Nasseri; Ali Allahresani; Batol Zakeri Nasab

Volume 3, Issue 2, pp. 72-147, Serial No. 7 , April 2015, , Pages 78-85

Abstract

  Microwave assisted green synthesis of α, ά- bis (substituted- benzylidene) alkanones by the crossed- aldol condensation reaction of substituted aryl aldehydes with ketones in the presence of catalytic amount of NbCl5 in good to excellent yields. This reaction is carried out under solvent-free ...  Read More Microwave assisted green synthesis of α, ά- bis (substituted- benzylidene) alkanones by the crossed- aldol condensation reaction of substituted aryl aldehydes with ketones in the presence of catalytic amount of NbCl5 in good to excellent yields. This reaction is carried out under solvent-free conditions. The results showed that aldehydes bearing electron–donating substituent's on phenyl-ring favored the formation of product in good to excellent yields with reaction times ranging between 3 and 7 min. In addition, furfural, cinamaldehyde, thiophene-2-carbaldehyde and 5-methylthiophene-2-carbaldehyde were investigated in aldol reaction, and the results showed excellent yields. Also, the reactions were carried out at room & thermal (80 0C) conditions. The results showed that the yields are in accordance with the microwave irradiations, But the time is 1.5-5 h at room temperature and 15-45 min in thermal conditions.

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Organic chemistry

Three-component procedure for the synthesis of new chiral spirooxindolopyrrolizidines via catalytic highly enantioselective 1,3-dipolar cycloaddition

Mohammad Javad Taghizadeh; Khosrow Jadidi

Volume 3, Issue 2, pp. 72-147, Serial No. 7 , April 2015, , Pages 96-104

Abstract

  The catalytic highly regio-, diastereo-, and enantioselective synthesis of a small library of spiropyrrolizidineoxindolesvia a four-component 1,3-dipolar cycloaddition reaction of azomethine ylides, derived from isatin, with electron-deficient dipolarophilewas described. The process occurs at room temperature ...  Read More The catalytic highly regio-, diastereo-, and enantioselective synthesis of a small library of spiropyrrolizidineoxindolesvia a four-component 1,3-dipolar cycloaddition reaction of azomethine ylides, derived from isatin, with electron-deficient dipolarophilewas described. The process occurs at room temperature in aqueous ethanol as a green solvent and in the presence of a bidendatebis(imine)–Cu(II)triflate complex as catalyst.The reaction mechanism is discussedon the basis of the assignment of the absolute configuration of the cycloadducts.The catalytic highly regio-, diastereo-, and enantioselective synthesis of a small library of spiropyrrolizidineoxindolesvia a four-component 1,3-dipolar cycloaddition reaction of azomethine ylides, derived from isatin, with electron-deficient dipolarophilewas described. The process occurs at room temperature in aqueous ethanol as a green solvent and in the presence of a bidendatebis(imine)–Cu(II)triflate complex as catalyst.The reaction mechanism is discussedon the basis of the assignment of the absolute configuration of the cycloadducts.

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Organic chemistry

A new facile route to synthesize thieno[3,2-e][1,2,4]triazolo[4,3-c]pyrimidine derivatives

Mehdi Soleimany; Jalil Lari; Hooshang Vahedi; Morteza Imanpour

Volume 3, Issue 2, pp. 72-147, Serial No. 7 , April 2015, , Pages 114-120

Abstract

  A new facile route for synthesis of 3- (aryl) -8, 9- di (alkyl) thieno [3,2-e] [1,2,4] triazolo pyrimidines derivative from the same starting material, 2- amino - 4,5 -di (alkyl) thiophene-3- carboxamide, has been developed through heterocyclization of the corresponding arylidene-hydrazino -5,6 -di (alkyl) ...  Read More A new facile route for synthesis of 3- (aryl) -8, 9- di (alkyl) thieno [3,2-e] [1,2,4] triazolo pyrimidines derivative from the same starting material, 2- amino - 4,5 -di (alkyl) thiophene-3- carboxamide, has been developed through heterocyclization of the corresponding arylidene-hydrazino -5,6 -di (alkyl) thieno [2,3-d] pyrimidine under refluxing condition with acetic anhydride followed by air oxidation. The products were obtained in high yield with an easy work-up in simple reaction along with the purification of products by non-chromatographic method. This general synthetic procedure can be extended to the preparation of a wide variety of isomeric triazoles using 2-amino thiophene-3-carboxamide bifunctional derivatives.

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Organic chemistry

Ammonium nitrate as an efficient and green reagent for the oxidation of alcohols into their corresponding carbonyl compounds in the presence of heteropoly acids

Vahid Azizkhani; Ali Ramazani; Sang Woo Joo

Volume 3, Issue 2, pp. 72-147, Serial No. 7 , April 2015, , Pages 121-131

Abstract

  Simple, cheap and green protocol for effective conversion of alcohols to corresponding carbonyl compounds in the presence of H14[NaP5W30O110] and ammonium nitrate is reported. The products were characterized by FT-IR and comparison of their physical properties with those reported in the literatures. ...  Read More Simple, cheap and green protocol for effective conversion of alcohols to corresponding carbonyl compounds in the presence of H14[NaP5W30O110] and ammonium nitrate is reported. The products were characterized by FT-IR and comparison of their physical properties with those reported in the literatures. The progress of the reaction was monitored by thin layer chromatography (TLC) technique. The aliphatic products were detected by gas chromatography–flame ionization detector. Reactions were completed within 15-35 minutes at room temperature. In order to investigate the catalyst reusability, the oxidation of benzyl alcohol was carried out in the presence of H14[NaP5W30O110]. At the end of each reaction, the catalyst was separated and the recovered catalyst was reused for at least three runs without significant degradation in catalytic activity and performance.

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Organic chemistry

Synthesis of methyl 2-[2-(alkylimino)-4-oxo-3-phenyl-1,3-thiazolan-5-yliden]acetate derivatives under solvent-free condition

Rahimeh Hajinasiri; Sobhan Rezayati

Volume 3, Issue 2, pp. 72-147, Serial No. 7 , April 2015, , Pages 132-136

Abstract

  An efficient synthesis of Methyl 2-[2-(alkylimino)-4-oxo-3-phenyl-1,3-thiazolan-5-yliden]acetate derivatives via simple three-component reaction and one-pot reactions between isoquinoline, dimethyl acetylenedicarboxylate and N-phenylthiourea under solvent-free conditions without using any additional ...  Read More An efficient synthesis of Methyl 2-[2-(alkylimino)-4-oxo-3-phenyl-1,3-thiazolan-5-yliden]acetate derivatives via simple three-component reaction and one-pot reactions between isoquinoline, dimethyl acetylenedicarboxylate and N-phenylthiourea under solvent-free conditions without using any additional catalyst, is described. The mild reaction conditions and good yields and exhibit the synthetic advantage of this method. Also this method is environmentally friendly. The methods of green chemistry continue to grow in importance. Alternative processes help to conserve resources and can even reduce costs. The replacement of convention solvents with water or solvent-free conditions, which is harmless to health and is available in large quantities. The thiazolium rings are key units in agricultural compounds and drugs.

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Organic chemistry

Oxidative aromatization of some 1,4-dihydropyridines by aqueous hydrogen peroxide in ethanol

Masoomeh Abdoli; Maryam Hajibabaiee

Volume 3, Issue 2, pp. 72-147, Serial No. 7 , April 2015, , Pages 143-147

Abstract

  Some 3, 5-diacyl or 3,5-diester 1,4-dihydropyridines were oxidized to the corresponding pyridine derivatives using hydrogen peroxide in aqueous ethanol in the presence of potassium bromide and acetic acid as the catalysts. The reaction was carried out in ethanol and products were isolated in high to ...  Read More Some 3, 5-diacyl or 3,5-diester 1,4-dihydropyridines were oxidized to the corresponding pyridine derivatives using hydrogen peroxide in aqueous ethanol in the presence of potassium bromide and acetic acid as the catalysts. The reaction was carried out in ethanol and products were isolated in high to excellent yields. However, oxidation of 3,5-diacetyl 1,4-dihydropyridines is slower than 3,5-diester 1,4-dihydropyridines under the same condition. Furhermore, the reaction is facilitated by electron releasing groups on 4-substituent of dihydropyridine ring. The cheapness of reagent, high yielding, easy workup and mild condition makes this method a useful addition to the available method in organic synthesis. In addition, employment of clean oxidant H2O2 together with nontoxic solvent ethanol makes it friendly to the environment.

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Organic chemistry

Furocoumarins from Heracleum rawianum in Iran

Fatemeh Mahmoudi Kordi; Hassan Valizadeh; Zahra Hosseinzadeh; Mir Babak Bahadori

Volume 3, Issue 1, pp. 1-71, Serial No.6 , January 2015, , Pages 1-5

Abstract

  The species Heracleum rawianum belongs to Apiaceae, is one of the native species in Iran. The leaves and fruits of Heracleum rawianium are used traditionally in Iran as flavouring agent and spice for food. In the present work, the extraction of aerial parts of this plant with acetone by maceration is ...  Read More The species Heracleum rawianum belongs to Apiaceae, is one of the native species in Iran. The leaves and fruits of Heracleum rawianium are used traditionally in Iran as flavouring agent and spice for food. In the present work, the extraction of aerial parts of this plant with acetone by maceration is described. Our phytochemical analysis of the chloroform extract of the aerial parts of this plant afforded three condensed furocoumarins. Furocoumarins such as angelicin (in remarkable amount), allobergapten and sphondin were isolated and identified by IR, 1H-NMR, 13C-NMR and DEPT-135 spectroscopic data, MS spectrometery and camparison with the literature. To the best of our knowledge, no phytochemical investigations on this species have been reported.

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Organic chemistry

The preparation of quinoxaline and 2,3-dihydropyrazine derivatives using selectfluor as an efficient and reusable catalyst

Seyedeh Fatemeh Hojati; Zahra Nematdoust; Toktam Zeinali

Volume 3, Issue 1, pp. 1-71, Serial No.6 , January 2015, , Pages 6-15

Abstract

  Selectfluor [1-(chloro methyl) -4-flouro -1,4-di azonia bicyclo[2,2,2] octane bis (tetraflouro-borate)] catalyzed the preparation of quinoxaline and 2,3-dihydo pyrazine derivatives through one -pot condensation of 1,2-di amines with 1,2-di carbonyls in solvent and under solvent- free conditions. This ...  Read More Selectfluor [1-(chloro methyl) -4-flouro -1,4-di azonia bicyclo[2,2,2] octane bis (tetraflouro-borate)] catalyzed the preparation of quinoxaline and 2,3-dihydo pyrazine derivatives through one -pot condensation of 1,2-di amines with 1,2-di carbonyls in solvent and under solvent- free conditions. This catalyst is commercially available, inexpensive, reusable, stable to air and moisture, and relatively non-toxic. Furthermore, very short reaction times, high yields of products, mild reaction conditions, absence of solvent, and easy work-up are other considerable advantages of these procedures. Also, a resonable mechanism has been proposed for the current reaction. The chemical structure and purity of the products were characterized by 1H NMR and IR spectroscopy.

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Organic chemistry

A novel synthesis of diastereomerically pure spiro- oxindolopyrrolizidines and oxindolopyrrolidines via cycloaddition reactions of azomethine ylides

Mohammad Javad Taghizadeh; Khosrow Jadidi

Volume 3, Issue 1, pp. 1-71, Serial No.6 , January 2015, , Pages 57-61

Abstract

  An efficient one-pot three-component procedure for the synthesis of new chiral spiro oxindolopyrrolidines/pyrrolizidines with highly regio- and diastereo-enantio, selective from 1,3-dipolar cycloaddition of azomethine ylides and chiral menthol-drived trans-cinnamic are described. The mechanism of the ...  Read More An efficient one-pot three-component procedure for the synthesis of new chiral spiro oxindolopyrrolidines/pyrrolizidines with highly regio- and diastereo-enantio, selective from 1,3-dipolar cycloaddition of azomethine ylides and chiral menthol-drived trans-cinnamic are described. The mechanism of the reaction is discussed on basis of the assignment of the absolute configuration of one of the cycloaddition products, which obtained by single crystal X-ray analysis. The process occurs at reflux temperature in ethanol as green solvent and in the absence of any bidentate chelating Lewis acids. Functionalized pyrrolidines and pyrrolizidines with spirooxindole ring systems are the central skeletons for numerous alkaloids and pharmacologically important compounds.1 Gelesmine, pseudotabersonine, formosanine, isoformosanine, morroniside and mitraphylline are some of the alkaloids containing spirooxindole ring systems.

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Organic chemistry

One-pot multicomponent reaction for the synthesis of 2-amino-4-chromenes promoted by 1-methyl imidazoliumiodide [mim]Cl ionic- liquid catalyst under solvent-free conditions

Mohammad Reza Poor Heravi; Mohammad Amirloo

Volume 3, Issue 1, pp. 1-71, Serial No.6 , January 2015, , Pages 62-71

Abstract

  A simple, clean, and environmentally benign three-component process for the synthesis of 2-amino-4Hchromenes using [mim]Cl, as an efficient catalyst under solvent-free conditions are described. A wide range of aromatic aldehydes easily undergoes condensations with 1-naphthol and malononitrile under solvent-free ...  Read More A simple, clean, and environmentally benign three-component process for the synthesis of 2-amino-4Hchromenes using [mim]Cl, as an efficient catalyst under solvent-free conditions are described. A wide range of aromatic aldehydes easily undergoes condensations with 1-naphthol and malononitrile under solvent-free conditions 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 work-up and good yields. Furthermore, the catalyst can be easily recovered and reused for at least five cycles without losing its activities.A simple, clean, and environmentally benign three-component process for the synthesis of 2-amino-4Hchromenes using [mim]Cl, as an efficient catalyst under solvent-free conditions are described. A wide range of aromatic aldehydes easily undergoes condensations with 1-naphthol and malononitrile under solvent-free conditions 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 work-up and good yields. Furthermore, the catalyst can be easily recovered and reused for at least five cycles without losing its activities.

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Organic chemistry

Isolation and characterization of curcumin from powdered rhizomes of turmeric plant marketed in Maragheh city of Iran with soxhlet technique

Mehdi Nabati; Mehrdad Mahkam; Hassan Heidari

Volume 2, Issue 4, pp. 236-325, Serial No. 5 , October 2014, , Pages 236-243

Abstract

  Turmeric (Curcuma longa L.) is extensively used as a spice, food preservative and colouring material. It has been used in traditional medicine for various diseases. Curcumin, the main yellow bioactive component of turmeric has been shown to have a wide spectrum of biological actions. Heretofore, it has ...  Read More Turmeric (Curcuma longa L.) is extensively used as a spice, food preservative and colouring material. It has been used in traditional medicine for various diseases. Curcumin, the main yellow bioactive component of turmeric has been shown to have a wide spectrum of biological actions. Heretofore, it has been reported that natural colored extracts isolated from turmeric rhizomes with many methods such as maceration, digestion, microwave and infusion. In this paper, it was tried to isolate and characterize curcumin from the curcumin rhizomes marketed in Maragheh city of Iran by soxhlet extraction technique in methanol solvent. The advantage of this technique is the isolation of large amounts of curcumin (208 mg from 25 g turmeric rhizomes powder) with smaller quantity of methanol.

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Organic chemistry

Isolation and structure elucidation of coumarin and cinamate derivatives from Lycium ruthenicum

Hassan Valizadeh; Fatemeh Mahmoodi Kordi; Reza Koohkan; Mir Babak Bahadori; Mehdi Moridi Farimani

Volume 2, Issue 4, pp. 236-325, Serial No. 5 , October 2014, , Pages 277-282

Abstract

  Lycium species is a popular medicinal plant in the traditional Chinese medicine and Lycium ruthenicum is a native medicinal plant of Iran. Lycium genus has several biologically important properties too. Investigation of chemical composition of ethyl acetate extract of this plant is the goal of this study. ...  Read More Lycium species is a popular medicinal plant in the traditional Chinese medicine and Lycium ruthenicum is a native medicinal plant of Iran. Lycium genus has several biologically important properties too. Investigation of chemical composition of ethyl acetate extract of this plant is the goal of this study. Two coumarins (Scopoletin and Sculetin) and Methyl-2-hydroxy-4-undecanoxy-trans-cinamate were isolated and characterized as the major constituents using 1H-NMR, 13C-NMR and FT- IR spectroscopic data, MS spectrometry, elemental analysis and by comparison with the literature values. Phytochemical investigation of Lycium ruthenicum demonstrated the presence of important biologically active compounds. This is the first phytochemical study of this species in Iran.

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Organic chemistry

Pharmacological properties of some 3-substituted indole derivatives, a concise overview

Kobra Nikoofar; Diba Kadivar; Samaneh Shirzadnia

Volume 2, Issue 4, pp. 236-325, Serial No. 5 , October 2014, , Pages 300-315

Abstract

  Indole is a nitrogen-containing heterocycle. It is a very important motif in agriculture and pharmacy. Many compounds containing indole moiety has been isolated form nature. It is also an important part in natural alkaloids. Tryptophan is an amino acid which posses indole. 3-Sustituted indoles are the ...  Read More Indole is a nitrogen-containing heterocycle. It is a very important motif in agriculture and pharmacy. Many compounds containing indole moiety has been isolated form nature. It is also an important part in natural alkaloids. Tryptophan is an amino acid which posses indole. 3-Sustituted indoles are the main group of its derivatives. Because the wide-spread application of 3-substituted indolic compounds their synthetic procedures are in demand by organic chemists. In this review we have focused on about twenty compound of 3-substituted indole derivatives that showed pharmacological properties. A concise synthetic route for some of them has also been reported. The main pharmaceutical properties of these compounds are antibacterial, anticancer and antimicrobial activities.

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Organic chemistry

One-pot and one-step novel N-methylation of 2,6-diaminopyridine

Mehdi Nabati; Mehrdad Mahkam

Volume 2, Issue 3, pp. 162-231, Serial No. 4 , July 2014, , Pages 162-167

Abstract

  2,6-diaminopyridine is extensively used as a pharmaceutical intermediate and a hair dye coupler as oxidation formulations. It is soluble in protic solvents. Primary and secondary amines are N-methylated by various methods such as direct alkylation of amines with Hofmann mechanism, but in many of these ...  Read More 2,6-diaminopyridine is extensively used as a pharmaceutical intermediate and a hair dye coupler as oxidation formulations. It is soluble in protic solvents. Primary and secondary amines are N-methylated by various methods such as direct alkylation of amines with Hofmann mechanism, but in many of these methods due to overalkylations, we earn a mixture of amino products. Consequently, they aren't selective in secondary amines preparation. Also, the selective synthesis of secondary amines is a problematic field in organic chemistry. 2,6-diaminopyridine can be selective N-methylated from reaction of this compound with sodium azide and orthoformic ester in low time with good yields.

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Organic chemistry

1-Carboxymethyl-3-methylimidazolium chloride {[cmmim]Cl} as an efficient catalyst for the solvent-free synthesis of bis(indolyl)methanes

Ahmad Reza Moosavi-Zare; Mahdi Pouraskar-Borazjani; Zahra Naz

Volume 2, Issue 3, pp. 162-231, Serial No. 4 , July 2014, , Pages 168-172

Abstract

  1-Carboxymethyl-3-methylimidazolium chloride {[cmmim]Cl} is utilized as a highly efficient and reusable catalyst for the synthesis of bis(indolyl)methanes by the condensation reaction of indole with arylaldehydes under solvent-free conditions at room temperature. In summary, the presented method have ...  Read More 1-Carboxymethyl-3-methylimidazolium chloride {[cmmim]Cl} is utilized as a highly efficient and reusable catalyst for the synthesis of bis(indolyl)methanes by the condensation reaction of indole with arylaldehydes under solvent-free conditions at room temperature. In summary, the presented method have several advantages including simplicity, low cost, generality, efficiency, clean reaction profile, high yield, short reaction time, ease of product isolation, mild reaction conditions, and good agreement with the green chemistry protocols. In this work, all aldehydes, including benzaldehyde and arylaldehydes possessing electron-withdrawing substituents, electron-releasing substituents and halogens on their aromatic ring, afforded the desired bis(indolyl)metanes in high to excellent yields and in short reaction times.

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Organic chemistry

Ag nanoparticle/melamine sulfonic acid supported on silica gel as an efficient catalytic system for synthesis of dihydropyrimidin thiones

Parya Nasehi; Alireza Kiasat; Mohammad Kazem Mohammadi

Volume 2, Issue 3, pp. 162-231, Serial No. 4 , July 2014, , Pages 180-186

Abstract

  3,4-dihydropyrimidin-2(1H)-thiones were synthesized in the presence of Ag nanoparticle/melamine sulfonic acid (MSA) supported on silica gel. The reaction was carried out at 110 oC for 20 min under solvent free conditions. In all cases, the three component reaction proceeded smoothly to give the corresponding ...  Read More 3,4-dihydropyrimidin-2(1H)-thiones were synthesized in the presence of Ag nanoparticle/melamine sulfonic acid (MSA) supported on silica gel. The reaction was carried out at 110 oC for 20 min under solvent free conditions. In all cases, the three component reaction proceeded smoothly to give the corresponding 3,4-dihydropyrimidin-2(1H)-thiones in moderate to good yield. We have found the best conditions are using 0.2 g MSA, 0.05 g Ag nanoparticle.SiO2 under solvent free conditions at 110 oC. This method have some advantages such as good yield, mild reaction conditions, ease of operation and work up, short reaction time and high product purity. In this work, we have investigated the application of Ag nanoparticle/MSA.SiO2 for synthesis of Biginelli – type condensation.

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Organic chemistry

Caesium carbonate as a highly efficient catalyst for the synthesis of macrocyclic diamides

Esmael Rostami; Maryam Bagherzadeh; Akram Khodadadi; Ay Soda Ghobadpoor; Fatemeh Dehghani; Zahra Heidari; Mahmood Feraidooni; Zahra Abshirini; Fatemeh Tavazo; Zahra Keshvarz

Volume 2, Issue 3, pp. 162-231, Serial No. 4 , July 2014, , Pages 187-195

Abstract

  In this research work, we report the synthesis of macrocyclic diamides from the reaction of diesters and aliphatic diamines in the presence of caesium carbonate. It has been demonstrated that among the carbonate of alkali metals (Li2CO3, Na2CO3, K2CO3 and CS2CO3), CS2CO3 appear to be the best catalyst ...  Read More In this research work, we report the synthesis of macrocyclic diamides from the reaction of diesters and aliphatic diamines in the presence of caesium carbonate. It has been demonstrated that among the carbonate of alkali metals (Li2CO3, Na2CO3, K2CO3 and CS2CO3), CS2CO3 appear to be the best catalyst for macrocyclization. Diesters with different substitution patterns on the aromatic ring reacted smoothly with diamines under optimal conditions, affording the corresponding macrocycles in high yields. Introducing a rigid group (e.g., sulfone) on the substrate led to somewhat decreased yield. Various substrates proved to be suitable for this macrocyclization reaction, especially, the flexible ones.

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Organic chemistry

Synthesis and characterization of novel silyl derivatives of curcumin

Mehdi Nabati; Mehrdad Mahkam

Volume 2, Issue 2, pp. 82-163, Serial No. 3 , April 2014, , Pages 129-136

Abstract

  Abstract:Turmeric is a member of the ginger family (Zingiberaceae), which is extensively used as a spice, food preservative and colouring material. Curcumin is a main bioactive natural compound derived from the rhizome of this plant. Curcumin can exist in several tautomeric forms, keto and enol. The ...  Read More Abstract:Turmeric is a member of the ginger family (Zingiberaceae), which is extensively used as a spice, food preservative and colouring material. Curcumin is a main bioactive natural compound derived from the rhizome of this plant. Curcumin can exist in several tautomeric forms, keto and enol. The keto form is more stable than enol form. Silyl ethers have proven to be versatile substrates for a wide variety of organic reactions and they are prepared by reacting an alcohol and a silicon halide using a base such as triethylamine in stoichiometric quantity. Curcumin silyl ether derivatives were prepared under mild conditions. The stability of products decreases with increasing size of the silyl substitutions and the products will be unstable.

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Organic chemistry

The SAMP-/RAMP -hydrazone methodology in asymmetric synthesis of 4S-ferrugineone and 4S, 5S-ferrugineol: The pheromones of palm weevils

Hamid Saeidian; Dieter Enders; Zohreh Mirjafary

Volume 2, Issue 2, pp. 82-163, Serial No. 3 , April 2014, , Pages 137-146

Abstract

  4S-ferrugineone and 4S,5S-ferrugineol as pheromones of palm weevils were synthesized in 3 and 4 steps, respectively, starting from nonane-5-one employing SAMP-/RAMP -hydrazone methodology. 5-nonanone is transformed to its corresponding RAMP hydrazone by reaction with the enantiomerically pure hydrazine ...  Read More 4S-ferrugineone and 4S,5S-ferrugineol as pheromones of palm weevils were synthesized in 3 and 4 steps, respectively, starting from nonane-5-one employing SAMP-/RAMP -hydrazone methodology. 5-nonanone is transformed to its corresponding RAMP hydrazone by reaction with the enantiomerically pure hydrazine RAMP. Metalation with lithium diisopropylamide (LDA) in ether to form azaenolate, followed by methylation with methyl iodide, furnishes the product hydrazone. Finally, cleavage of the hydrazone moiety to regenerate the carbonyl functionality is possible by ozonolysis, leads to the 4S-ferrugineone. The crucial step would be the final diastereoselective reduction to the 4S, 5S-ferrugineol.The 4S, 5S-ferrugineol has been obtained with better yield (71%) and good disteromeric excess 40% de at -78 °C.

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Organic chemistry

Efficient classical synthesis of aminoazines under microwave irradiation

Seyed Mohammad Vahdat; Abbas Mohammadzadeh; Esmaiel Derafshian; Somaieh Akhoondi

Volume 2, Issue 2, pp. 82-163, Serial No. 3 , April 2014, , Pages 157-163

Abstract

  In the present study, Aminoazines were prepared from the reaction of amidrazone hydroiodide with various aromatic aldehydes in the presence of a solid base under microwave irradiation with power level of 850 W for 2-7 min in high yields. The amidrazone hydroiodide can also be prepared by the reaction ...  Read More In the present study, Aminoazines were prepared from the reaction of amidrazone hydroiodide with various aromatic aldehydes in the presence of a solid base under microwave irradiation with power level of 850 W for 2-7 min in high yields. The amidrazone hydroiodide can also be prepared by the reaction of S-methyl isothiobenzamide hydroiodide and hydrazine in methanol under nitrogen gas. All synthesized compounds were characterized on the basis of IR and 1H NMR spectral data. The significant features of this method are short reaction times, high yields of the products, solvent free reaction, easy work-up procedure, directly production of aminoazines.

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Organic chemistry

Synthesis and characterization of derived imines from 4-imino-5,6,7,8-tetrahydro-1-benzothieno[2,3-d]pyrimidin-3(4H)-amine

Mehdi Soleimany; Jalil Lari; Hooshang Vahedi

Volume 2, Issue 1, pp. 1-81, Serial No. 2 , January 2014, , Pages 18-26

Abstract

  The synthesis and characterization of derived imines from 4-imino-5,6,7,8-tetrahydro-1-benzo thieno[2,3-d]pyrimidin-3(4H)-amine 3 has been developed in 3 steps through the reaction of heteroaromatic o-aminonitrile 1 with triethyl orthoformate afforded the corresponding imido ester 2 followed by cyclization ...  Read More The synthesis and characterization of derived imines from 4-imino-5,6,7,8-tetrahydro-1-benzo thieno[2,3-d]pyrimidin-3(4H)-amine 3 has been developed in 3 steps through the reaction of heteroaromatic o-aminonitrile 1 with triethyl orthoformate afforded the corresponding imido ester 2 followed by cyclization with hydrazine hydrate to furnish iminothienopyrimidineamine 3 and finally the imination of 3 at room temperature with aromatic aldehydes was generated the corresponding imines (5a-5h). The new products were obtained in high yield with an easy work-up in simple reaction along with the purification of products by non-chromatographic method. This general synthetic procedure can be extended to the preparation of wide variety of imines using o-aminonitrile bifunctional derivatives which synthesized by Gewald reaction.

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Organic chemistry

Isolation, identification and characterization of lawsone from henna leaves powder with soxhlet technique

Mehrdad Mahkam; Mehdi Nabati; Hadieh Rahbar Kafshboran

Volume 2, Issue 1, pp. 1-81, Serial No. 2 , January 2014, , Pages 34-38

Abstract

  Lawsone a natural pigment present in the henna leaves has been used as a skin and hair dye since 1400 BC. The concentration of this natural compound in leaves varies from place to place depending upon many of the environmental factors and the highest quantity reported so far is about 1% of the dry mass. ...  Read More Lawsone a natural pigment present in the henna leaves has been used as a skin and hair dye since 1400 BC. The concentration of this natural compound in leaves varies from place to place depending upon many of the environmental factors and the highest quantity reported so far is about 1% of the dry mass. Heretofore, it has been reported that natural colored extracts and isolate from Henna leaves with many methods such as maceration, digestion, microwave and infusion. In this paper, regarding the therapeutic effects and traditional applications of henna, it was tried to isolate and characterize Lawsone from the henna leaves marketed in Tabriz city of Iran by soxhlet extraction technique in methanol solvent. The advantage of this technique is the isolation of large amounts of lawsone (720 mg from 40 g henne leaves powder) with smaller quantity of methanol.

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Organic chemistry

Potassium carbonate: a highly efficient catalyst for the acylation of alcohols, phenols and thiols under mild conditions

Mostafa Kazemi; Homa Kohzadi; Zahra Noori

Volume 2, Issue 1, pp. 1-81, Serial No. 2 , January 2014, , Pages 39-47

Abstract

  A general, mild and efficient protocol has been developed for the synthesis of esters and thioesters. The process has been taking place using tetra n-butylammonium iodide (TBAI) as a phase-transfer catalyst and in the presence of potassium carbonate (K2CO3). A wide range of esters and thioesters was ...  Read More A general, mild and efficient protocol has been developed for the synthesis of esters and thioesters. The process has been taking place using tetra n-butylammonium iodide (TBAI) as a phase-transfer catalyst and in the presence of potassium carbonate (K2CO3). A wide range of esters and thioesters was prepared in high yields and suitable times by the treatment of alcohols, phenols and thiols with acetic anhydride. Acylation reactions of a number of alcohols, phenols and thiols with acetic anhydride demonstrated that Potassium carbonate is a convenient and efficient catalyst for the synthesis of esters and thioesters. This is a mild, general and practical procedure for the synthesis of esters and thioesters in high yields and suitable times.

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