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991.
Guang-Feng Hong Zhen-Hua Dong Yong-Mei Xiao Pu Mao Ling-Bo Qu 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):771-779
AbstractA practical metal-free procedure for the synthesis of (E)-vinyl sulfones has been developed through the coupling of β-nitrostyrenes with sodium sulfinates under microwave irradiation. This methodology provides a convenient and efficient approach to various (E)-vinyl sulfones from readily available starting materials with excellent regioselectivity. The present oxidative reaction involves an efficient denitrative radical cross-coupling of β-nitrostyrenes with sodium sulfinates via using AcOH as an additive. 相似文献
992.
Omer Tahir Gunkara 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):909-916
AbstractThe regioselective synthesis of Polyhedral oligomeric silsesquioxane (POSS)-based norbornyl imide derivatives through palladium catalyzed Heck coupling reaction was reported on an effective synthetic method to organic–inorganic bio-hybrids serving as advanced materials. The reaction of POSS-based imide derivatives with various aryl iodides catalyzed by palladium acetate in the presence of triethyl amine, as the base, in DMF afforded the products in moderate yields. All new POSS derivatives were structurally characterized by FTIR, 1H, 13C NMR, HRMS and GC/MS analyses. 相似文献
993.
Sebastian Wagner Muriel Rakotomalala Frederick Chesneau Thomas Zevaco Manfred Döring 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):781-798
Abstract Organophosphorus compounds such as 6H-dibenzo[c,e][1,2]oxaphosphinine 6-oxide (DOPO, 1) and its derivatives are important and versatile compounds for a broad field of applications. However, a thorough spectral assignment is often subordinate to its chemical properties. This article presents and unambiguously attributes the 1H and 13C NMR spectra of DOPO (1), selected products yielded from the Atherton–Todd reaction (2–4), DOPO-HQ (5) as well as sulfur derivatives (6–7) via a set of 1D- and 2D-NMR experiments. The complex P-C and P-H coupling patterns are discussed and compared with the derivatives possessing different chemical environments around the phosphorus atom. In addition, we compared our results with density functional theory calculations. Even though the prediction of NMR data of organophosphorus compounds via molecular modeling is limited, this study presents a method that yields good results for this class of heterocycles. This knowledge should help to quickly assign NMR spectroscopic data of other DOPO (1) derivatives and can be extrapolated to organophosphorus compounds in general. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental resource: NMR Spectra of Compounds 1-7 (Figures S1 - S15). 相似文献
994.
Xiao-Bo Ma Jing-Lin Zhang 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):227-231
Abstract The condensation of N-phenyl-N′-(2-hydroxylphenyl)urea or N-phenyl-N′-(2-aminophenyl)urea with tris(dia1kylamino)phosphine afforded derivatives of 4,5-benzo-1,3,2-oxaza (or diaza)-phospholane which formed intramolecular hydrogen bond. The cleavage of the amide bond to give N,N-dialky1-N′-phenylurea together with polymers of 1,3,2-benzodiazaphosphole was observed in the latter reaction. 相似文献
995.
DIHALOCARBENE ADDITION TO ARYLSUBSTTTUTED VINYL PHOSPHATES UNDER PHASE TRANSFER CATALYTIC CONDITIONS
Imre Petneházy György Keglevich László Tőke 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-2):77-82
Abstract Dihalocarbene addition to aryl-substituted vinyl phosphates was carried out both in solid-liquid and in liquid-liquid two phase systems. The dihalocyclopropane adducts of vinyl phosphates could be obtained in better yield using dihalocarbenes generated by the latter method and no hydrolysis of the vinyl phosphate and of the adduct occurred under these circumstances. Eighteen new vinyl phosphate-dihalocarbene adducts were synthetized and characterized. 相似文献
996.
Keiji Tanino Isao Kuwajima 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):369-370
Highly stereoselective C-C bond forming reactions were developed on the basis of nucleophilic addition of alkenylsulfides to aldehydes, imines, and α,β-unsaturated carbonyl compounds. 相似文献
997.
Türsen Demir Frederick J. Raveney Robert A. Shaw 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):155-163
Abstract The reactions of 4-methyl-2-[N-(p-toluidinyl)methyl]aniline with phosphorus oxychloride, thiophosphoryl chloride, and their derivatives yield 1,3,2-benzodiazaphosphorine 2-oxides and 2-sulphides. Their 1H NMR and infrared spectra are discussed. Related 1,3,2-benzodiazophosphorine and 1,3,2-dibenzodiazaphosphocine 2-oxides and 2-sulphides are compared. 相似文献
998.
Robabeh Baharfar Nasim Porahmad 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):1988-1996
Abstract Synthesis of polyfunctionalized ketenimines via three-component reactions of rhodanine and 5-(4-dimethylaminobenzylidene)-rhodanine with dialkyl acetylenedicarboxylates and alkyl isocyanides is described. The reactions proceed smoothly under mild conditions leading to the desired products in good yields. In the case of methyl acetylenecarboxylate, the reaction led to methyl (Z)-3-({5-[(E)-1-(tert-butylamino)methylidene]-4-oxo-4,5-dihydro-1,3-thiazol-2-yl}sulfanyl)-2-propenoate in low yield. GRAPHICAL ABSTRACT 相似文献
999.
Microwave (MW) radiation has been used in chemical analysis and chemical synthesis. MW heating under controlled conditions offers distinct advantages over conventional heating. The reactions are carried out in environmentally clean and safe solvents and in many cases, reactions can be carried out under solvent‐free conditions. This method of synthesis has grown rapidly and found its use in various sectors. This paper reviews some of the reactions that have been accelerated with higher yields under MW irradiation. The application of MW‐assisted synthesis in the medicinal and pharmaceutical industries will be emphasized. 相似文献
1000.
New strategy was developed for the preparation of the photoresponsive polymers containing azo-chromophores as side-groups from the active chlorine atoms of polyvinyl chloride (PVC). The anilinated polyvinyl chloride precursors, anilinated polyvinyl chloride (PVC-An) and o-chloroanilinated polyvinyl chloride (PVC-oClAn), synthesized chemically by reacting PVC with sodium aniline (o-chloroaniline) salt. Then the two novel PVC-based polymers functionalized with azo-chromophores (PVC-AZ-An and PVC-o-AZ-NP) were synthesized via the azo-coupling reactions of the anilinated polyvinyl chloride precursors (PVC-An and PVC-oClAn) with the diazonium salts of aniline and alpha naphthylamine, respectively. The structures of polymers were confirmed by FTIR and 1H–NMR. The UV-Vis spectra of the obtained polymer in THF solution showed that the π ?π ? absorption band of PVC-o-AZ-NP shifted to longer wavelength (red-shifted) due to the influence of auxochrome (-Cl) compared to the π ?π ? absorption band of PVC-AZ-An. 相似文献