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1.
Ali Reza Kiasat Foad Kazemi Mehdi Fallah Mehr Jardi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):1841-1844
A simple and efficient method for the conversion of various oxiranes to the corresponding thiiranes using thiourea under solvent free conditions is described. 相似文献
2.
We report an ecofriendly synthetic approach for the fabrication of biogenic gold nanoparticles (AuNPs) using electron-rich sea cucumber extract as a bio-reductant and stabilizing agent in reducing gold cations into AuNPs at the optimal conditions. The produced AuNPs are spherical in shape with an average particle size of 11 ± 1.5 nm in transmission electron microscopy (TEM) and exhibited a crystal structure of face-centered cubic in X-ray diffraction (XRD) analyses. Our results indicated that bioinspired AuNPs demonstrate superior catalytic activity in the safe and facile one-pot synthesis of polyhydroquinoline derivatives under solvent-free reaction conditions. This green route encompasses multiple benefits including highly recyclable bioinspired catalyst (5 cycles), short reaction times, convenient workout, high to excellent product yields (82%–97%), and nonhazardous conditions. 相似文献
3.
Ahmad R. Massah Davood Azadi Hamid Aliyan Ahmad R. Momeni Hamid Javaherian Naghash Foad Kazemi 《Monatshefte für Chemie / Chemical Monthly》2008,139(3):233-240
Summary. The preparation of N-acylsulfonamides is described using primary amines, arylsulfonyl chlorides and acyl chlorides. Reaction of primary aryl amines
with arylsulfonyl chlorides in the presence of NaHCO3 produced N-arylsulfonamides, which reacted in situ with benzoyl chloride furnishing the corresponding N-benzoyl-N-arylsulfonamides in 72–96% yields. Accordingly, 4-nitrobenzoyl chloride and 3,5-dinitrobenzoyl chloride were used as acylating
agents. All the reactions were carried out under solvent-free conditions at room temperature and the products were isolated
after simple work-up in high yields and purity. 相似文献
4.
Mohamed Hilmy Elnagdi Ramadan Maawad Abdel-Motaleb Mona Mustafa Mohamed Foad Zayed Eman Moustafa Kamel 《Journal of heterocyclic chemistry》1987,24(6):1677-1681
The behaviour of several 2-amino-3-cyano-4H-pyran derivatives toward a variety of nucleophilic reagents is reported. 相似文献
5.
Foad Kazemi Ali Reza Kiasat 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):1333-1337
Epoxids are efficiently converted to the corresponding thiiranes by ammonium thiocyanate (NH 4 SCN) in the presence of catalytic amounts of oxalic acid with excellent isolated yields under mild and nonaqueous reaction conditions. This conversion performed under both conventional heating and microwave conditions. Distinct rate enhancement is observed under microwave irradiation. 相似文献
6.
Size, purity, yield, and morphology of arc-synthesized nanosteel particles are altered by the employed currents (50, 80, and 100?A/cm2), as well as the media [nitrogen, open air, ethylene glycol, and distilled water saturated with polyvinylpyrrolidone (PVP)]. Nanoparticles (Nps) produced at 80?A/cm2 in distilled water, PVP-saturated distilled water, and ethylene glycol are on average five times smaller than those synthesized in nitrogen and open air. This is attributed to the capping as well as stabilizing effects of the liquid media. Changing current from 50 to 80?A/cm2 results in a decrease of Nps sizes in the liquid media, and a size increase in the gaseous media, which suffer from the lack of grain growth and particle aggregation prohibitor agents. SEM images and XRD profiles show the purest nanosteel particles formed in nitrogen, with an average size of 29?nm at 50?A/cm2. Nps with relatively smaller size (7?nm) are obtained in distilled water at 100?A/cm2, as a mixture of nanosteel and nano Fe3O4 particles. Yet, comparatively the highest amounts of the latter are formed in the open air at 80?A/cm2. 相似文献
7.
Thao T. P. Nguyen Dr. Foad Raji Dr. Cuong V. Nguyen Dr. Ngoc N. Nguyen Prof. Anh V. Nguyen 《Chemphyschem》2023,24(23):e202300062
Surfactants are used to control the macroscopic properties of the air-water interface. However, the link between the surfactant molecular structure and the macroscopic properties remains unclear. Using sum-frequency generation spectroscopy and molecular dynamics simulations, two ionic surfactants (dodecyl trimethylammonium bromide, DTAB, and sodium dodecyl sulphate, SDS) with the same carbon chain lengths and charge magnitude (but different signs) of head groups interact and reorient interfacial water molecules differently. DTAB forms a thicker but sparser interfacial layer than SDS. It is due to the deep penetration into the adsorption zone of Br− counterions compared to smaller Na+ ones, and also due to the flip-flop orientation of water molecules. SDS alters two distinctive interfacial water layers into a layer where H+ points to the air, forming strong hydrogen bonding with the sulphate headgroup. In contrast, only weaker dipole-dipole interactions with the DTAB headgroup are formed as they reorient water molecules with H+ point down to the aqueous phase. Hence, with more molecules adsorbed at the interface, SDS builds up a higher interfacial pressure than DTAB, producing lower surface tension and higher foam stability at a similar bulk concentration. Our findings offer improved knowledge for understanding various processes in the industry and nature. 相似文献
8.
Sodium borohydride supported on alumina reduces imines to the corresponding secondary amines in high to excellent isolated yields under solvent-free conditions. Noteworthy is that highly chemoselective reactions were achieved in the presence of other functional groups such as halogen, nitro, and cyano groups. 相似文献
9.
M.Z. Kassaee S. Soleimani-Amiri F. Buazar H. Aref Rad 《Journal of Molecular Structure》2009,893(1-3):48-55
Following our quest for silylenes and germylenes, we have reached at W shaped novel triplet disilyleno- and digermylenocarbenes through optimization of 2,3-di(X)disilacyclopropenylidenes and 2,3-di(X)digermacyclopropenylidenes, respectively, at five ab initio and DFT levels (M = Si, Ge; X = H, F, Cl, Br). Also, we have met the challenge of confining SiSi double bonds in singlet cyclopropenylidene ground states by optimizing singlet 2,3-di(X)disilacyclopropenylidenes, at the same levels of theory. Results are compared and contrasted to the corresponding singlet and triplet 2,3-di(X)cyclopropenylidenes. 相似文献
10.