Jakarta, Indonesia
Jakarta, Indonesia
Time filter
Source Type

Sadeghian S.,Institute for Research in Fundamental Sciences | Sadeghian S.,Azzahra University | Sheikh-Jabbari M.M.,Institute for Research in Fundamental Sciences | Vahidinia M.H.,Institute for Research in Fundamental Sciences | Yavartanoo H.,CAS Institute of Theoretical Physics
Nuclear Physics B | Year: 2015

We study the near horizon structure of Extremal Vanishing Horizon (EVH) black holes, extremal black holes with vanishing horizon area with a vanishing one-cycle on the horizon. We construct the most general near horizon EVH and near-EVH ansatz for the metric and other fields, like dilaton and gauge fields which may be present in the theory. We prove that (1) the near horizon EVH geometry for generic gravity theory in generic dimension has a three dimensional maximally symmetric subspace; (2) if the matter fields of the theory satisfy strong energy condition either this 3d part is AdS3, or the solution is a direct product of a locally 3d flat space and a d-3 dimensional part; (3) these results extend to the near horizon geometry of near-EVH black holes, for which the AdS3 part is replaced with BTZ geometry. We present some specific near horizon EVH geometries in 3, 4 and 5 dimensions for which there is a classification. We also briefly discuss implications of these generic results for generic (gauged) supergravity theories and also for the thermodynamics of near-EVH black holes and the EVH/CFT proposal. © 2015.

Heravi M.M.,Azzahra University | Tavakoli-Hoseini N.,Islamic Azad University at Mashhad | Bamoharram F.F.,Islamic Azad University at Mashhad
Synthetic Communications | Year: 2011

A simple, clean, and environmentally benign three-component process for the synthesis of amidoalkyl naphthols using Brnsted acidic ionic liquids as efficient catalysts in solution and under solvent-free conditions is described. Copyright © Taylor & Francis Group, LLC.

Sulfonic acid-functionalized silica-coated nano-Fe3O4 particles (Fe3O4@SiO2-SO3H) have been prepared as a novel heterogeneous acid using a facile process. The material was subsequently identified as an efficient catalyst for the synthesis of a variety of tetraketone derivatives via the Knoevenagel condensation and Michael addition reactions of aromatic aldehydes to dimedone, 1,3-indanedione, and 1,3-dimethyl barbituric acid. The catalyst could be readily recovered using a simple external magnet and reused several times without any significant loss in activity. The current catalytic process is both sustainable and economical because it operates under aqueous conditions, the catalyst can be recovered and reused, and the reactions themselves require only a short time and provide the products in high yield.

Heravi M.M.,Azzahra University | Fazeli A.,Azzahra University
Heterocycles | Year: 2010

This brief review represents the synthesis of heterocyclic compounds via application of Heck reaction in recent years. © The Japan Institute of Heterocyclic Chemistry.

Heravi M.M.,Azzahra University | Asadi S.,Azzahra University
Tetrahedron Asymmetry | Year: 2012

The asymmetric aldol reaction is one of the most powerful synthetic tools for carbon-carbon bond-forming reactions. This method provides a beneficial route to access chiral β-hydroxy carbonyl compounds, which are versatile synthetic motifs found in biologically active natural products and pharmaceutically attractive intermediates. The aim of this review is to provide an overview of the many contributions and recent advances in the field of organocatalytic asymmetric aldol reactions. © 2012 Elsevier Ltd. All rights reserved.

Heravi M.M.,Azzahra University | Hashemi E.,Azzahra University
Monatshefte fur Chemie | Year: 2012

Palladium-catalyzed reactions are key steps for the formation of carbon-carbon bonds in modern synthetic chemistry and among these reactions few have influenced organic synthesis as greatly as the Suzuki-Miyaura reaction which was first reported in 1979. This review highlights recent and major developments of this approach in intramolecular cyclization and heterocyclization reactions. © Springer-Verlag 2012.

Javid A.,Islamic Azad University at Mashhad | Heravi M.M.,Azzahra University | Bamoharram F.F.,Islamic Azad University at Mashhad
E-Journal of Chemistry | Year: 2011

A highly efficient one-pot synthesis of 1,8-dioxo-octahydroxanthenes from dimedone and various aromatic aldehydes under reflux conditions in water, catalyzed by silica-supported preyssler nano particles (SPNP) is reported. The products were formed in excellent yields and the acidic catalyst was completely heterogeneous and can be recycled for many times. © Copyright E-Journal of Chemistry 2004-2011.

Heravi M.M.,Azzahra University | Alinejhad H.,Azzahra University | Bakhtiari K.,Azzahra University | Oskooie H.A.,Azzahra University
Molecular Diversity | Year: 2010

Three-component one-pot synthesis of some novel 10-aryl-7,7-dimethyl-6,7,8, 10-tetrahydro-9H-[1,3]-dioxolo[4,5-b]xanthen-9-ones, which have not been published before, and 12-aryl-9,9-dimethyl-8,9,10,12-tetrahydro-11H-benzo[a] xanthen-11-ones from condensation of 3,4-methylenedioxyphenol or β-naphthol, aldehydes and dimedone under solvent-free conditions at 120 °C is reported. © 2009 Springer Science+Business Media B.V.

Davoodnia A.,Islamic Azad University at Mashhad | Heravi M.M.,Azzahra University | Safavi-Rad Z.,Islamic Azad University at Mashhad | Tavakoli-Hoseini N.,Islamic Azad University at Mashhad
Synthetic Communications | Year: 2010

3-Methyl-1-(4-sulfonic acid)butylimidazolium hydrogen sulfate [(CH 2)4SO3HMIM][HSO4], a Brnsted acidic ionic liquid, has been used as an efficient, green, and reusable catalyst for the synthesis of 1,2,4,5-tetrasubstituted imidazoles using benzil, an aromatic aldehyde, and a primary amine in the presence of ammonium acetate under solvent-free conditions. The catalyst could be recycled and reused several times without noticeably decreasing the catalytic activity. © Taylor & Francis Group, LLC.

Heravi M.M.,Azzahra University | Derikvand F.,Azzahra University | Ranjbar L.,Azzahra University
Synthetic Communications | Year: 2010

An efficient and convenient approach is reported for three-component, one-pot synthesis of the [1,2,4]triazolo/benzimidazolo quinazolinones by condensation of 2-amino benzimidazole or 3-amino-1,2,4-triazole as amine sources with dimedone and different aldehydes in the presence of sulfamic acid as a reusable, green catalyst in acetonitrile and under heating conditions.

Loading Azzahra University collaborators
Loading Azzahra University collaborators