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1.
Shadpour E. Mallakpour Abdol‐Reza Hajipour Ali‐Reza Mahdavian Sepideh Khoee 《Journal of polymer science. Part A, Polymer chemistry》1999,37(8):1211-1219
The reaction of N‐phthaloyl‐L ‐leucine acid chloride (1) with isoeugenol (2) was carried out in chloroform, and novel optically active isoeugenol ester derivative 3 as a chiral monomer was obtained in high yield. Compound 3 was characterized by 1H‐NMR, IR, and mass and elemental analysis and then was used for the preparation of model compound 5 and polymerization reactions. 4‐Phenyl‐1,2,4‐triazoline‐3,5‐dione, PhTD (4), was allowed to react with compound 3. The reaction is very fast and gives only one diastereomer of 5 via Diels–Alder and ene pathways in quantitative yield. In order to explain this diastereoselectivity, a nonconcerted two‐step mechanism involving benzylic cation (BC) and aziridinium (AI) have been proposed for the Diels–Alder and ene reactions, respectively. The polymerization reactions of novel monomer 3 with bis(triazolinedione)s [bis(p‐3,5‐dioxo‐1,2,4‐triazolin‐4‐ylphenyl)methane (8) and 1,6‐bis(3,5‐dioxo‐1,2,4‐triazolin‐4‐yl)hexane] (9)] were performed in N,N‐dimethylacetamide (DMAc) at room temperature. The reactions are exothermic, fast, and gave novel optically active polymers 10 and 11 via repetitive Diels–Alder–ene polyaddition reactions. These polymers have inherent viscosities in a range about 0.18–0.22 dL/g. Some physical properties and structural characterizations of these new polymers have been studied and are reported. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 1211–1219, 1999 相似文献
2.
In this paper, we show that the existence of immersions preserving given geometric structures between manifolds can be expressed in terms of a relation between suitably constructed moving coframes on the manifolds, and we show that the key steps in Cartan's method of equivalence can be extended to yield necessary conditions for the existence of such immersions. 相似文献
3.
Khoee Sepideh Bafkary Reza Fayyazi Faeze 《Journal of Sol-Gel Science and Technology》2017,81(2):493-504
Journal of Sol-Gel Science and Technology - pH-responsive chitosan-coated graphene oxide-mesoporous silica nanoparticles (GMSN-Cs) was synthesized as a core–shell nanosheets to be used as DOX... 相似文献
4.
A novel and efficient method is described for the immediate oxidation of different organosulfur compounds using tetrabutylammonium peroxymonosulfate in the presence of manganese meso-tetraphenylporphyrin and imidazole. The method is highly chemoselective and the yields are excellent. 相似文献
5.
Farhad Shirini Mohammad A. Zolfigol Abdol-Reza Abri 《中国化学快报》2008,19(1):51-54
Fe(NO3)3-9H2O/Fe(HSO4)3 was used as an efficient reagent system for the oxidation of alcohols to their corresponding carbonyl compounds. All reactions were performed in the absence of solvent in good to high yields. Under the same reaction conditions, thiols and sulfides were also converted to their corresponding disulfides and sulfoxides, respectively. 2007 Farhad Shirini. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved. 相似文献
6.
Shadpour E. Mallakpour Abdol-Reza HajipourSepideh Khoee 《European Polymer Journal》2002,38(10):2011-2016
4,4′-(Hexafluoroisopropylidene)-N,N′-bis(phthaloyl-l-leucine-p-amidobenzoic acid) (2) was prepared from the reaction of 4,4′-(hexafluoroisopropylidene)-N,N′-bis(phthaloyl-l-leucine) diacid chloride with p-aminobenzoic acid. The direct polycondensation reaction of monomer (2) with p-phenylenediamine (2a), 4,4′-diaminodiphenylsulfone (2b), 2,4-diaminotoluene (2c), 2,6-diaminopyridine (2d), m-phenylene diamine (2e), benzidine (2f), 4,4′-diaminodiphenylether (2g) and 4,4′-diaminodiphenyl methane (2h) was carried out in a medium consisting of triphenyl phosphite, N-methyl-2-pyrolidone, pyridine, and calcium chloride. The homogeneous mixture was heated at 220 °C for 1 min under nitrogen. The resulting poly(amide-imide)s (PAIs) having inherent viscosities 0.27-0.78 dl/g were obtained in high yield and are optically active and thermally stable. All of the above polymers were fully characterized by IR spectroscopy, elemental analyses and specific rotation. Some structural characterization and physical properties of this new optically active PAIs are reported. 相似文献
7.
Abdol-Reza Mansouri 《Comptes Rendus Mathematique》2004,339(1):39-42
In this Note, we show that contrary to the dimension 3 case, isotropic contact sub-Riemannian manifolds of dimension greater than 3 do not exist. To cite this article: A.-R. Mansouri, C. R. Acad. Sci. Paris, Ser. I 339 (2004). 相似文献
8.
Abstract
A new dimeric ortho-palladated complex of 2-methoxyphenethylamine was synthesized and characterized and its application as a cyanation catalyst was investigated. The main advantages of this catalyst are its easy preparation, handling, stability, and moisture insensitivity. Thus, [Pd{C6H3(CH2CH2NH2)-4-OMe-5-κ 2-C,N}(μ-Br)]2 showed excellent catalytic activity for the cyanation of aryl iodides and bromides with K4[Fe(CN)6], in DMF in the presence of K2CO3 under microwave irradiation and conventional heating at 130 °C to give the desired cyanoarene products in good to high yields. The less reactive aryl chlorides also react with K4[Fe(CN)6] to give moderate yields of the aromatic nitriles. The effects of various parameters such as solvent, base, and amount of catalyst were studied. The reaction is suitable for a wide variety of substituted aryl halides with different electronic properties. Application of microwave irradiation improved the yields of the reactions and reduced the reaction times from hours to minutes. 相似文献9.
Shadpour E. Mallakpour Abdol‐Reza Hajipour Sepideh Khoee 《Journal of polymer science. Part A, Polymer chemistry》2000,38(7):1154-1160
A new facile and rapid polycondensation reaction of 4,4′‐(hexafluoroisopropylidene)‐N,N′‐bis(phthaloyl‐L‐leucine) diacid chloride (1) with several aromatic diamines, including benzidine (2a), 4,4′‐diaminodiphenyl methane (2b), 1,5‐diaminoanthraquinone (2c), 4,4′‐sulfonyldianiline (2d), 3,3′‐diaminobenzophenone (2e), P‐phenylenediamine (2f), 2,6‐diaminopyridine (2g), 4,4′‐diaminobenzophenone (2h), 2,4‐diaminotoluene (2i), and 4,4′‐diaminodiphenylether (2j), was developed with a domestic microwave oven in the presence of a small amount of a polar organic medium such as o‐cresol. The polymerization reactions proceeded rapidly compared to conventional solution polycondensation and finished within 12 min, producing a series of optically active poly(amide‐imide)s with quantitative yields and high inherent viscosities of 0.50–1.93 dL/g. All of the polymers were fully characterized by IR, elemental analyses, and specific rotation. Some structural characterization and physical properties of these optically active poly(amide‐imide)s are reported. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 1154–1160, 2000 相似文献
10.
Farhad Shirini Mohammad A. Zolfigol Abdol-Reza Abri 《Monatshefte für Chemie / Chemical Monthly》2008,139(1):17-20
Summary. Alcohols and phenols are efficiently converted to their corresponding trimethylsilyl ethers with hexamethyldisilazane (HMDS) in the presence of Fe(HSO4)3 in solution and under solvent-free conditions. 相似文献