Ardeshir Khazaei - Academia.edu (original) (raw)
Papers by Ardeshir Khazaei
A highly efficient procedure for the synthesis of triarylmethane and diarylmethane via benzylatio... more A highly efficient procedure for the synthesis of triarylmethane and diarylmethane via benzylation of aromatic hydrocarbons from benzyl alcohols using supported P2O5 on SiO2 and/or Al2O3 under solvent-free conditions is described. Excellent yields of triarylmethane and diarylmethane were obtained using P2O5-SiO2 (50% W/W) and/or P2O5-Al2O3 (50% W/W) at room temperature. The reusability of both supported P2O5 on SiO2 and Al2O3 were examined. Both supported reagents show favorable activities in first and second runs, however, a decline in reactivity was observed in following attempts. The reaction is scalable to >0.03 mole amounts.Keywords: Diarylmethane, triarylmethane, aromatic alcohol, P2O5, silica gel, alumin
ACS Applied Materials & Interfaces, 2019
Achieving green and sustainable chemical processes by replacing organic solvents with water has a... more Achieving green and sustainable chemical processes by replacing organic solvents with water has always been one of the green chemistry goals and a challenging topic for chemists. However, the poor solubility of organic materials is a major limitation to achieving this goal, especially in alcohol oxidation. In this contribution, the development and design of amphiphilic catalysts via abundant, safe, cheaper, and more biocompatible sources have received notable attention. To this purpose, herein, our group successfully synthesized a new multifunctional amphiphilic carbon quantum dot (CQD) composed of 1-aminopropyl-3-methyl-imidazolium chloride ([APMim][Cl]), dodecylamine (DDA), and citric acid (CA)
Bulletin of the Korean Chemical Society, 2012
Molecules, 2002
Deprotections of 2,4-dinitrophenylhydrazones to their corresponding carbonyl compounds have been ... more Deprotections of 2,4-dinitrophenylhydrazones to their corresponding carbonyl compounds have been carried out in good yields by using N,N ′-dibromo-N,N ′-1,2-ethanediylbis(p-toluenesulphonamide) (BNBTS, 2) under microwave irradiation.
Acta Crystallographica Section C Crystal Structure Communications, 2001
The title compound, N,N'-difluoro-N,N'-ethylenedi-p-toluenesulfonamide, C(16)H(18... more The title compound, N,N'-difluoro-N,N'-ethylenedi-p-toluenesulfonamide, C(16)H(18)F(2)N(2)O(4)S(2).CHCl(3), is a novel stable compound of the N-F class of reagents containing two R(2)N-F functionalities. The compound, as the chloroform solvate, is the first such bis(N-F) compound to be structurally characterized. It adopts a solid-state structure in which the two aromatic rings are antiperiplanar and a combination of weak C-H...F and C-H...O hydrogen bonds [distances and angles range from 3.265 (4) to 3.439 (4) A and 150 to 170 degrees, respectively] and pi-stacking between the rings of different molecules (separations of 3.717 and 3.926 A) results in a solid-state structure containing well defined channels in which CHCl(3) solvent molecules are located. The N-F distances are 1.428 (3) and 1.433 (3) A.
Journal of the Brazilian Chemical Society, 2013
Sistemas de liberação de fármacos baseados em conjugados polímero-fármaco fornecem um tratamento ... more Sistemas de liberação de fármacos baseados em conjugados polímero-fármaco fornecem um tratamento melhorado com menor toxidade ou efeitos colaterais e são usados no tratamento de diferentes doenças. Conjugados de poli(estireno-alt-anidrido maleico) (PSMA) biodegradável, com agentes terapêuticos tais como cloridrato de amantadina, amlopidina, gabapentina, zonisamida e mesalamina, foram gerados pela formação de ligações de amidas dos fármacos amino que reagiram com os grupos anidridos do PSMA. As quantidades de fármacos covalentemente conjugados foram determinadas por ressonância magnética nuclear (NMR) de 1 H, e a taxa de liberação in vitro em solução tampão (pH 1.3) foi estudada à temperatura do corpo (37 o C). Em estudos de cinética, modelos de dissolução diferentes foram examinados a fim de se obter dados de liberação do fármaco e os dados coletados se ajustaram bem a equação de Korsmeyer-Peppas, revelando um mecanismo de difusão Fickaniano dominante na liberação do fármaco em condições in vitro. Drug delivery systems based on polymer-drug conjugates give an improved treatment with lower toxicity or side effects and be used for the treatment of different diseases. Conjugates of biodegradable poly(styrene-alt-maleic anhydride) (PSMA), with a therapeutic agents such as amantadine hydrochloride, amlodipine, gabapentin, zonisamide and mesalamine, were afforded by the formation of the amide bonds of the amino drugs that reacted with the PSMA anhydride groups. The amounts of covalently conjugated drugs were determined by a 1 H NMR spectroscopic method, and the in vitro release rate in buffer solution (pH 1.3) was studied at body temperature 37 °C. In kinetic studies, different dissolution models were examined to obtain drug release data and the collected data were well-fitted to the Korsmeyer-Peppas equation, revealing a dominant Fickian diffusion mechanism for drug release under the in vitro conditions.
Journal of the Brazilian Chemical Society, 2013
Aldeídos e cetonas são intermediários importantes principalmente na construção de esqueletos carb... more Aldeídos e cetonas são intermediários importantes principalmente na construção de esqueletos carbônicos. A oxidação de álcoois é tão importante que um grande número de métodos e reagentes foi relatado com essa proposta. Reagentes N-halo são amplamente utilizados em síntese inorgânica e como continuação do nosso interesse na aplicação de compostos N-halo em síntese inorgânica, dibromo dimetilidantoína (DBDMH) e dicloro dimetilidantoína (DCDMH) foram usados na oxidação de álcoois e nosso trabalho em andamento está baseado no desenvolvimento de protocolos de oxidação altamente eficientes. Observamos a oxidação de álcoois secundários com quantidades estequiométricas de DBDMH e DCDMH em condições livre de solventes, na faixa de temperatura de 70-80 ºC. Aldehydes and ketones are important intermediates, especially for the construction of carbonskeletons. The oxidation of alcohols is so important that a large number of methods and reagents have been reported for this purpose. N-halo reagents are widely used in organic synthesis and as a continuation of our interest in the application of N-halo compounds in organic synthesis, dibromo dimethylhydantoin (DBDMH) and dichloro dimethylhydantoin (DCDMH) were used for the oxidation of alcohols and our ongoing work on development of highly efficient oxidation protocols. We observed the oxidation of secondary alcohols with stoichiometric amounts of DBDMH and DCDMH under solvent-free conditions in the range of temperature 70-80 ºC.
![Research paper thumbnail of Rapid and highly efficient trimethylsilylation of alcohols and phenols with hexamethyldisilazane (HMDS) catalyzed by reusable zirconyl triflate, [ZrO(OTf)2]](https://attachments.academia-assets.com/104339911/thumbnails/1.jpg)
](Journal of Organometallic Chemistry, 2008
In this paper, rapid and efficient trimethylsilylation of alcohols and phenols with hexamethyldis... more In this paper, rapid and efficient trimethylsilylation of alcohols and phenols with hexamethyldisilazane in the presence of catalytic amounts of ZrO(OTf) 2 is reported. Primary, secondary and tertiary alcohols as well as phenols were efficiently converted to their corresponding TMS ethers in short reaction times at room temperature. It is noteworthy that this method can be used for chemoselective silylation of primary alcohols in the presence of secondary and tertiary alcohols and phenols.
The Journal of Organic Chemistry, 2000
A number of aldehydes and ketones were prepared by oxidation of alcohol by N,N-dichloro-4methylbe... more A number of aldehydes and ketones were prepared by oxidation of alcohol by N,N-dichloro-4methylbenzenesulfonamide under mild and neutral conditions in good to high yield in dichloromethane at room temperature.
The Journal of Organic Chemistry, 1993
The formation of hydrazone derivatives is a common method for the isolation and purification of c... more The formation of hydrazone derivatives is a common method for the isolation and purification of carbonyl compounds; purification of these derivatives followed by regeneration of the parent ketone is a good procedure for isolation of the desired ketone from a complex mixture.' A number of procedures are available for the regeneration of carbonyls from hydrazones. However, it is known that direct hydrolysis and/or exchange methods, as catalyzed by strong acids, can lead to condensation byproducts or hydrolysis of sensitive protecting groups.'S2 In these cases, viable alternatives may consist of methods of oxidative cleavage in organic solvents, or oxidative hydrolysis using a variety of reagents,112 including peroxides.2w On the other hand, oxidations of organic substrates employing dioxiranes (a new class of powerful oxidants), either in situ3 or separated in solution, of their parent ketone4 often carry the advantages of high selectivity, mild reaction conditions, and ease of product isolation. Most commonly, dioxiranes employed are of the type R(CH3)-C02 (1). Thus, dimethyldioxirane (la: R = CHd4a-C and the more reactive methyl(trifluoromethy1)dioxirane (lb: R = CF3)a*e have been applied to perform a variety of synthetic transformations,5 including regeneration of the carbonyl moiety from acetals, ketals, and orthoesters,6 as well as from Fischer-carbene c~mplexes.~ Along these lines, quite recently it has been shown8 that tosylhydrazones can be cleaved to the corresponding carbonyl compounds using dimethyldioxirane generated in situ from the reaction of acetone with potassium * To whom correspondence should be addressed. + In partial fulfillment of the requiremente for the Ph.D. degree.
Online Journal Abstract Information - Sabinet Online.
Chemistry - A European Journal, 2008
Iranian Polymer Journal, 1996
Bulletin of the Chemical Society of Japan, 1994
Iranian Polymer Journal, 2003
Chinese Chemical Letters, 2010
The first catalytic application of p-TsCl for efficient acetylation of various types of alcohols ... more The first catalytic application of p-TsCl for efficient acetylation of various types of alcohols and phenols with acetic anhydride in both solution and solvent-free conditions is reported. Also structurally diverse alcohols were formylated using formic acid based on the use of catalytic amount of p-TsCl under solvent-free condition. The reactions were carried out in short reaction time and in good to excellent yields at room temperature.
Efficient oxidation of various types of structurally diverse alcohols to the corresponding carbon... more Efficient oxidation of various types of structurally diverse alcohols to the corresponding carbonyl compounds can be carried out with N,N'-dibromo-N,N'-1,2-ethanediylbis(benzenesulphonamide) in good to high yield of products in CH 2 Cl 2 at room temperature. Primary (aliphatic, benzylic and allylic) alcohols are oxidized with no over-oxidation to carboxylic acids.
Catalysis …, 2007
... Synth. Commun., 29 (1999), p. 541. [15] B. Karimi and B. Golshani. J. Org. Chem., 65 (2000), ... more ... Synth. Commun., 29 (1999), p. 541. [15] B. Karimi and B. Golshani. J. Org. Chem., 65 (2000), p. 7228. [16] N. Azizi and MR Saidi. Organometallics, 23 (2004), p. 1457. [17] ZH Zhang, TS Li, F. Yang and CG Fu. Synth. Commun., 28 (1998), p. 3105. ...
Journal of the Brazilian …, 2006
Álcoois de estruturas diversas foram acetilados com anidrido acético, através de reações limpas e... more Álcoois de estruturas diversas foram acetilados com anidrido acético, através de reações limpas e eficientes, usando-se quantidade catalítica de N,N-dicloro-4-metilbenzenossulfonamida em diclorometano. Todas as reações ocorreram a temperatura ambiente, com rendimentos de bons a excelentes. Structurally diverse alcohols were acetylated in a clean and efficient reaction with acetic anhydride based on the use of a catalytic amount of N,N-dichloro-4-methylbenzenesulphonimide in dichloromethane. All reactions were performed at room temperature in good to excellent yields.
Acta Crystallographica Section C Crystal Structure Communications, 2001
The title compound, N,N'-difluoro-N,N'-ethylenedi-p-toluenesulfonamide, C(16)H(18... more The title compound, N,N'-difluoro-N,N'-ethylenedi-p-toluenesulfonamide, C(16)H(18)F(2)N(2)O(4)S(2).CHCl(3), is a novel stable compound of the N-F class of reagents containing two R(2)N-F functionalities. The compound, as the chloroform solvate, is the first such bis(N-F) compound to be structurally characterized. It adopts a solid-state structure in which the two aromatic rings are antiperiplanar and a combination of weak C-H...F and C-H...O hydrogen bonds [distances and angles range from 3.265 (4) to 3.439 (4) A and 150 to 170 degrees, respectively] and pi-stacking between the rings of different molecules (separations of 3.717 and 3.926 A) results in a solid-state structure containing well defined channels in which CHCl(3) solvent molecules are located. The N-F distances are 1.428 (3) and 1.433 (3) A.
A highly efficient procedure for the synthesis of triarylmethane and diarylmethane via benzylatio... more A highly efficient procedure for the synthesis of triarylmethane and diarylmethane via benzylation of aromatic hydrocarbons from benzyl alcohols using supported P2O5 on SiO2 and/or Al2O3 under solvent-free conditions is described. Excellent yields of triarylmethane and diarylmethane were obtained using P2O5-SiO2 (50% W/W) and/or P2O5-Al2O3 (50% W/W) at room temperature. The reusability of both supported P2O5 on SiO2 and Al2O3 were examined. Both supported reagents show favorable activities in first and second runs, however, a decline in reactivity was observed in following attempts. The reaction is scalable to >0.03 mole amounts.Keywords: Diarylmethane, triarylmethane, aromatic alcohol, P2O5, silica gel, alumin
ACS Applied Materials & Interfaces, 2019
Achieving green and sustainable chemical processes by replacing organic solvents with water has a... more Achieving green and sustainable chemical processes by replacing organic solvents with water has always been one of the green chemistry goals and a challenging topic for chemists. However, the poor solubility of organic materials is a major limitation to achieving this goal, especially in alcohol oxidation. In this contribution, the development and design of amphiphilic catalysts via abundant, safe, cheaper, and more biocompatible sources have received notable attention. To this purpose, herein, our group successfully synthesized a new multifunctional amphiphilic carbon quantum dot (CQD) composed of 1-aminopropyl-3-methyl-imidazolium chloride ([APMim][Cl]), dodecylamine (DDA), and citric acid (CA)
Bulletin of the Korean Chemical Society, 2012
Molecules, 2002
Deprotections of 2,4-dinitrophenylhydrazones to their corresponding carbonyl compounds have been ... more Deprotections of 2,4-dinitrophenylhydrazones to their corresponding carbonyl compounds have been carried out in good yields by using N,N ′-dibromo-N,N ′-1,2-ethanediylbis(p-toluenesulphonamide) (BNBTS, 2) under microwave irradiation.
Acta Crystallographica Section C Crystal Structure Communications, 2001
The title compound, N,N'-difluoro-N,N'-ethylenedi-p-toluenesulfonamide, C(16)H(18... more The title compound, N,N'-difluoro-N,N'-ethylenedi-p-toluenesulfonamide, C(16)H(18)F(2)N(2)O(4)S(2).CHCl(3), is a novel stable compound of the N-F class of reagents containing two R(2)N-F functionalities. The compound, as the chloroform solvate, is the first such bis(N-F) compound to be structurally characterized. It adopts a solid-state structure in which the two aromatic rings are antiperiplanar and a combination of weak C-H...F and C-H...O hydrogen bonds [distances and angles range from 3.265 (4) to 3.439 (4) A and 150 to 170 degrees, respectively] and pi-stacking between the rings of different molecules (separations of 3.717 and 3.926 A) results in a solid-state structure containing well defined channels in which CHCl(3) solvent molecules are located. The N-F distances are 1.428 (3) and 1.433 (3) A.
Journal of the Brazilian Chemical Society, 2013
Sistemas de liberação de fármacos baseados em conjugados polímero-fármaco fornecem um tratamento ... more Sistemas de liberação de fármacos baseados em conjugados polímero-fármaco fornecem um tratamento melhorado com menor toxidade ou efeitos colaterais e são usados no tratamento de diferentes doenças. Conjugados de poli(estireno-alt-anidrido maleico) (PSMA) biodegradável, com agentes terapêuticos tais como cloridrato de amantadina, amlopidina, gabapentina, zonisamida e mesalamina, foram gerados pela formação de ligações de amidas dos fármacos amino que reagiram com os grupos anidridos do PSMA. As quantidades de fármacos covalentemente conjugados foram determinadas por ressonância magnética nuclear (NMR) de 1 H, e a taxa de liberação in vitro em solução tampão (pH 1.3) foi estudada à temperatura do corpo (37 o C). Em estudos de cinética, modelos de dissolução diferentes foram examinados a fim de se obter dados de liberação do fármaco e os dados coletados se ajustaram bem a equação de Korsmeyer-Peppas, revelando um mecanismo de difusão Fickaniano dominante na liberação do fármaco em condições in vitro. Drug delivery systems based on polymer-drug conjugates give an improved treatment with lower toxicity or side effects and be used for the treatment of different diseases. Conjugates of biodegradable poly(styrene-alt-maleic anhydride) (PSMA), with a therapeutic agents such as amantadine hydrochloride, amlodipine, gabapentin, zonisamide and mesalamine, were afforded by the formation of the amide bonds of the amino drugs that reacted with the PSMA anhydride groups. The amounts of covalently conjugated drugs were determined by a 1 H NMR spectroscopic method, and the in vitro release rate in buffer solution (pH 1.3) was studied at body temperature 37 °C. In kinetic studies, different dissolution models were examined to obtain drug release data and the collected data were well-fitted to the Korsmeyer-Peppas equation, revealing a dominant Fickian diffusion mechanism for drug release under the in vitro conditions.
Journal of the Brazilian Chemical Society, 2013
Aldeídos e cetonas são intermediários importantes principalmente na construção de esqueletos carb... more Aldeídos e cetonas são intermediários importantes principalmente na construção de esqueletos carbônicos. A oxidação de álcoois é tão importante que um grande número de métodos e reagentes foi relatado com essa proposta. Reagentes N-halo são amplamente utilizados em síntese inorgânica e como continuação do nosso interesse na aplicação de compostos N-halo em síntese inorgânica, dibromo dimetilidantoína (DBDMH) e dicloro dimetilidantoína (DCDMH) foram usados na oxidação de álcoois e nosso trabalho em andamento está baseado no desenvolvimento de protocolos de oxidação altamente eficientes. Observamos a oxidação de álcoois secundários com quantidades estequiométricas de DBDMH e DCDMH em condições livre de solventes, na faixa de temperatura de 70-80 ºC. Aldehydes and ketones are important intermediates, especially for the construction of carbonskeletons. The oxidation of alcohols is so important that a large number of methods and reagents have been reported for this purpose. N-halo reagents are widely used in organic synthesis and as a continuation of our interest in the application of N-halo compounds in organic synthesis, dibromo dimethylhydantoin (DBDMH) and dichloro dimethylhydantoin (DCDMH) were used for the oxidation of alcohols and our ongoing work on development of highly efficient oxidation protocols. We observed the oxidation of secondary alcohols with stoichiometric amounts of DBDMH and DCDMH under solvent-free conditions in the range of temperature 70-80 ºC.
Journal of Organometallic Chemistry, 2008
In this paper, rapid and efficient trimethylsilylation of alcohols and phenols with hexamethyldis... more In this paper, rapid and efficient trimethylsilylation of alcohols and phenols with hexamethyldisilazane in the presence of catalytic amounts of ZrO(OTf) 2 is reported. Primary, secondary and tertiary alcohols as well as phenols were efficiently converted to their corresponding TMS ethers in short reaction times at room temperature. It is noteworthy that this method can be used for chemoselective silylation of primary alcohols in the presence of secondary and tertiary alcohols and phenols.
The Journal of Organic Chemistry, 2000
A number of aldehydes and ketones were prepared by oxidation of alcohol by N,N-dichloro-4methylbe... more A number of aldehydes and ketones were prepared by oxidation of alcohol by N,N-dichloro-4methylbenzenesulfonamide under mild and neutral conditions in good to high yield in dichloromethane at room temperature.
The Journal of Organic Chemistry, 1993
The formation of hydrazone derivatives is a common method for the isolation and purification of c... more The formation of hydrazone derivatives is a common method for the isolation and purification of carbonyl compounds; purification of these derivatives followed by regeneration of the parent ketone is a good procedure for isolation of the desired ketone from a complex mixture.' A number of procedures are available for the regeneration of carbonyls from hydrazones. However, it is known that direct hydrolysis and/or exchange methods, as catalyzed by strong acids, can lead to condensation byproducts or hydrolysis of sensitive protecting groups.'S2 In these cases, viable alternatives may consist of methods of oxidative cleavage in organic solvents, or oxidative hydrolysis using a variety of reagents,112 including peroxides.2w On the other hand, oxidations of organic substrates employing dioxiranes (a new class of powerful oxidants), either in situ3 or separated in solution, of their parent ketone4 often carry the advantages of high selectivity, mild reaction conditions, and ease of product isolation. Most commonly, dioxiranes employed are of the type R(CH3)-C02 (1). Thus, dimethyldioxirane (la: R = CHd4a-C and the more reactive methyl(trifluoromethy1)dioxirane (lb: R = CF3)a*e have been applied to perform a variety of synthetic transformations,5 including regeneration of the carbonyl moiety from acetals, ketals, and orthoesters,6 as well as from Fischer-carbene c~mplexes.~ Along these lines, quite recently it has been shown8 that tosylhydrazones can be cleaved to the corresponding carbonyl compounds using dimethyldioxirane generated in situ from the reaction of acetone with potassium * To whom correspondence should be addressed. + In partial fulfillment of the requiremente for the Ph.D. degree.
Online Journal Abstract Information - Sabinet Online.
Chemistry - A European Journal, 2008
Iranian Polymer Journal, 1996
Bulletin of the Chemical Society of Japan, 1994
Iranian Polymer Journal, 2003
Chinese Chemical Letters, 2010
The first catalytic application of p-TsCl for efficient acetylation of various types of alcohols ... more The first catalytic application of p-TsCl for efficient acetylation of various types of alcohols and phenols with acetic anhydride in both solution and solvent-free conditions is reported. Also structurally diverse alcohols were formylated using formic acid based on the use of catalytic amount of p-TsCl under solvent-free condition. The reactions were carried out in short reaction time and in good to excellent yields at room temperature.
Efficient oxidation of various types of structurally diverse alcohols to the corresponding carbon... more Efficient oxidation of various types of structurally diverse alcohols to the corresponding carbonyl compounds can be carried out with N,N'-dibromo-N,N'-1,2-ethanediylbis(benzenesulphonamide) in good to high yield of products in CH 2 Cl 2 at room temperature. Primary (aliphatic, benzylic and allylic) alcohols are oxidized with no over-oxidation to carboxylic acids.
Catalysis …, 2007
... Synth. Commun., 29 (1999), p. 541. [15] B. Karimi and B. Golshani. J. Org. Chem., 65 (2000), ... more ... Synth. Commun., 29 (1999), p. 541. [15] B. Karimi and B. Golshani. J. Org. Chem., 65 (2000), p. 7228. [16] N. Azizi and MR Saidi. Organometallics, 23 (2004), p. 1457. [17] ZH Zhang, TS Li, F. Yang and CG Fu. Synth. Commun., 28 (1998), p. 3105. ...
Journal of the Brazilian …, 2006
Álcoois de estruturas diversas foram acetilados com anidrido acético, através de reações limpas e... more Álcoois de estruturas diversas foram acetilados com anidrido acético, através de reações limpas e eficientes, usando-se quantidade catalítica de N,N-dicloro-4-metilbenzenossulfonamida em diclorometano. Todas as reações ocorreram a temperatura ambiente, com rendimentos de bons a excelentes. Structurally diverse alcohols were acetylated in a clean and efficient reaction with acetic anhydride based on the use of a catalytic amount of N,N-dichloro-4-methylbenzenesulphonimide in dichloromethane. All reactions were performed at room temperature in good to excellent yields.
Acta Crystallographica Section C Crystal Structure Communications, 2001
The title compound, N,N'-difluoro-N,N'-ethylenedi-p-toluenesulfonamide, C(16)H(18... more The title compound, N,N'-difluoro-N,N'-ethylenedi-p-toluenesulfonamide, C(16)H(18)F(2)N(2)O(4)S(2).CHCl(3), is a novel stable compound of the N-F class of reagents containing two R(2)N-F functionalities. The compound, as the chloroform solvate, is the first such bis(N-F) compound to be structurally characterized. It adopts a solid-state structure in which the two aromatic rings are antiperiplanar and a combination of weak C-H...F and C-H...O hydrogen bonds [distances and angles range from 3.265 (4) to 3.439 (4) A and 150 to 170 degrees, respectively] and pi-stacking between the rings of different molecules (separations of 3.717 and 3.926 A) results in a solid-state structure containing well defined channels in which CHCl(3) solvent molecules are located. The N-F distances are 1.428 (3) and 1.433 (3) A.