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101.
Erdal Ertas Hakan Bildirir Onur Sahin Ipek Oksen 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):1835-1844
Abstract Syntheses of two analogues of tetrathiafulvalene (TTF), fused to 1,4-dithiin and thiophene rings, substituted with thiophene moieties, have been illustrated. The syntheses were accomplished through the reaction of a 1,8-diketone with phosphorus pentasulfide or Lawesson's reagent in boiling dry toluene. Conversion of the thioketones to their the oxo forms with mercury (II) acetate, was followed by self-coupling in freshly distilled boiling triethyl phosphite. Attempts for their electro-polymerizations through the thiophene groups at the peripherals were unsuccessful. Computational chemistry studies revealed that the thiophene groups did not exhibit enough spin densities to perform polymerization. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. 相似文献
102.
采用电喷雾电离质谱通过直接进样方式对合成的3个含硫的三联吡啶配体及2个钌配合物进行分析,详细研究了其在电喷雾条件下的质谱行为。结果表明,含有芳硫基和苄硫基的三联吡啶配体在电喷雾过程中采取了不同的断裂方式,前者首先从与芳硫键相连的碳硫键断裂失去不含硫的部分碎片离子,而后者则从苄基碳硫键断裂失去含硫的部分碎片离子。两类配体与钌形成的配合物均具有较稳定的结构,不易发生多级质谱断裂。通过对配合物分子离子峰和同位素峰的分析讨论,确定了含硫的三联吡啶合钌配合物的结构。这一研究结果表明电喷雾多级串联质谱适合于含硫三联吡啶类配体及其钌配合物的结构研究,方法简便高效、准确可靠,为该类化合物的结构研究提供了参考。 相似文献
103.
Yuko Mochizuki Shinsuke Inagaki Mayu Suzuki Jun Zhe Min Koichi Inoue Kenichiro Todoroki Toshimasa Toyo'oka 《Journal of separation science》2013,36(12):1883-1889
A novel bromoquinolinium reagent, i.e. 1‐(3‐aminopropyl)‐3‐bromoquinolinium bromide (APBQ), was synthesized for the analysis of carboxylic acids. A simple and practical precolumn derivatization procedure using the APBQ in RP chromatography and MS (HPLC‐MS) has been developed using bile acids and free fatty acids, as the representative carboxylic acids in biological samples. The APBQ efficiently reacted with carboxylic acids at 60°C for 60 min in the presence of N,N‐dicyclohexylcarbodiimide and pyridine as the activation reagents. Because the APBQ possesses a bromine atom in the structure, the identification of a series of carboxylic acids was easily achieved due to the characteristic bromine isotope pattern in the mass spectra. The APBQ also has a quaternary amine structure, thus the positively charged derivatives are predominate for the highly sensitive detection of carboxylic acids. The APBQ was successfully applied to the selective determination of biological carboxylic acids in human plasma. The bile acids (chenodeoxycholic acid and deoxycholic acid) and several saturated (stearic acid and palmitic acid) and unsaturated free fatty acids (oleic acid and linoleic acid) were reasonably determined by HPLC‐MS under the proposed procedure. Based on the results of analyses of human plasma and saliva, the proposed procedure using APBQ seems to be applicable for the qualitative and quantitative analyses of a series of carboxylic acids in biological samples. 相似文献
104.
Synthesis of new benzoxazaphosphinine/benzoxazaphosphole/diazaphosphaphenalene 2‐sulfides were accomplished by the reaction of Lawesson's reagent (LR) with 4‐bromo‐2‐[(phenylamino) methyl]phenol (1a), 4‐bromo‐2‐[(4‐chloro/bromo/methoxy/methylphenyl‐amino)methyl]phenol (1b–e), 4‐bromo‐2‐[(benzylamino)methyl]phenol (1f), 2‐amino‐4‐chlorophenol (2a)/2‐amino‐4‐methylphenol (2b), 1,8‐diaminonaphthalene (3) respectively in anhydrous toluene. Products 4a–f, 5a–b and 6 were characterized by IR, 1H, 13C, 31P NMR and Mass spectra. 相似文献
105.
Polysubstituted allylic amines were regio- and stereoselectively synthesized by a one-pot tandem reaction of Cu(I)-catalyzed carbomagnesiation of acetylenic sulfones and its further reaction with N-tosylimine. 相似文献
106.
Reaction of 2-pyridylmagnesium chlorides with N,N-dialkyl arylamides afford exclusively 2-(aroyl) pyridines in high yields and purity without the formation of any tertiary alcohol. This method employs easily available raw materials and avoids the use of hazardous lithium reagents and cryogenic conditions. Further, preferential reactivity of this Grignard reagent with N,N-dialkyl arylamides over its carbonitrile counterparts offers a variety of 2-(aroyl) pyridines including the ones containing carbonitrile groups on the aryl ring. 相似文献
107.
A novel protocol for intramolecular ketyl-olefin radical cyclization with low-valent titanium reagent is outlined. It allows the formation of the benzopyran nucleus from ortho-allyloxy propiophenones as the sole product in moderate yields via intramolecular radical cyclization. 相似文献
108.
Seetaram Mohapatra Chittaranjan Bhanja Satyaban Jena Subhendu Chakroborty Sabita Nayak 《合成通讯》2013,43(15):1993-2007
The Bestmann–Ohira reagent serves as a versatile platform for the regioselective construction of pyrazoles, triazoles, and oxazoles via a cycloaddition reaction and multicomponent reaction. In this review, we have summarized the most significant advances in the Bestmann–Ohira reagent (BOR)–assisted construction of functionalized five–membered heterocycles reported in the literature up to 2012. 相似文献
109.
110.
Mohammad Ghaffarzadeh Mohammad Bolourtchian Zohreh Hassanzadeh Fard Mohammad Reza Halvagar Farshid Mohsenzadeh 《合成通讯》2013,43(14):1973-1981
One‐step microwave‐assisted synthesis of phenylacetylenes 2a–j from the corresponding ketones 1a–j in the presence of a new reagent, PCl5–pyridine, is described. The reaction is carried out under a simple operational and experimental procedure, avoiding the use of the complicated and harsh multistep reaction. 相似文献