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61.
Nitration of aromatic halides proceeded smoothly in the presence of catalytic amounts of Cu bronze and N,N′-dimethylethylenediamine. Sodium nitrite-18-crown-6, or tetra-n-butylammonium nitrite (n-Bu4NNO2) turned out to be efficient nitrating agents. The aromatic nitro compounds were synthesized under essentially neutral conditions. 相似文献
62.
Mohammad Bakherad Ali Keivanloo Zahra Kalantar Vahid Keley 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):464-470
Abstract Reaction of 2-mercaptopropargylquinazoline-4-one with various aryliodides catalyzed by Pd–Cu leads to the regioselective formation of 1-arylsubstituted-5H-[1,3]thiazolo-[3,2-a]quinazoline-5-ones. GRAPHICAL ABSTRACT 相似文献
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K. Rajender Reddy M. Venkateshwar C. Uma Maheswari P. Santhosh Kumar 《Tetrahedron letters》2010,51(16):2170-1420
An efficient synthesis of 1-iodoalkynes and iodophenols was easily achieved by employing simple KI and TBHP. The reaction does not involve the use of a metal and base combination. A variety of substituted alkynes and phenols were prepared with good to excellent yield. 相似文献
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Ciguatoxin C-CTX-1 was isolated as a principal causative toxin of ciguatera seafood poisoning in the Caribbean Sea, and is structurally classified as a ladder-shaped polycyclic ether. In this Letter, we report the synthesis of the tricyclic LMN-ring system of C-CTX-1. SmI2-mediated reductive cyclization efficiently constructed the seven-membered M-ring with the axially oriented 1,3-dimethyl structure. 相似文献
68.
The C-C coupling reaction between ethyl acetoacetate and aryl halides in the presence of CuI is described. The effects of solvent, ligands such as vicinal diamines and amino acids, base and temperature are reported. The arylated acetoacetate ester is deacylated under the reaction conditions resulting in the generation of 2-arylacetic acid esters, constituting a mild alternative to direct arylation of carboxylate esters. 相似文献
69.
A simple one-pot procedure for the direct conversion of alcohols into azides using TsIm 总被引:1,自引:0,他引:1
A facile and efficient method for one-pot conversion of alcohols into azides using N-(p-toluenesulfonyl)imidazole (TsIm) is described. In this method, alcohols are refluxed with a mixture of NaN3, TsIm and triethylamine in the presence of catalytic amounts of tetra-n-butylammonium iodide (TBAI) in DMF affording the corresponding alkyl azides in good yields. This methodology is highly efficient for various structurally diverse alcohols with selectivity for ROH: 1° > 2° > 3°. 相似文献
70.
Unprecedented Efficient Structure Controlled Phosphorescence of Silver(I) Clusters Stabilized by Carba‐closo‐dodecaboranylethynyl Ligands 下载免费PDF全文
Michael Hailmann Natalia Wolf Rebecca Renner Thomas C. Schäfer Benjamin Hupp Dr. Andreas Steffen Prof. Dr. Maik Finze 《Angewandte Chemie (International ed. in English)》2016,55(35):10507-10511
{Ag2(12‐C≡C‐closo‐1‐CB11H11)}n and selected pyridine ligands have been used for the synthesis of photostable AgI clusters that, with one exception, exhibit for AgI compounds unusual room‐temperature phosphorescence. Extraordinarily intense phosphorescence was observed for a distorted pentagonal bipyramidal AgI7 cluster that shows an unprecedented quantum yield of Φ=0.76 for AgI clusters. The luminescence properties correlate with the structures of the central AgIn motifs as shown by comparison of the emission properties of the clusters with different numbers of AgI ions, different charges, and electronically different pyridine ligands. 相似文献