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Interlocked Systems in Catalysis and Switching
Published in Jubaraj Bikash Baruah, Principles and Advances in Supramolecular Catalysis, 2019
The construction of a rotaxane through catalytic reactions based on an active site on a cyclic macrocycle is illustrated in Figure 4.2. A cyclic derivative of 1,2-cyclohexyldiamine 4.2a forms a copper (I) complex 4.2b upon reaction with copper iodide. This complex, with a catalytic amount of cesium carbonate, reacts with an amide derivative, thereby forms the complex 4.2c. This copper(I) complex 4.2c has a deprotonated amide coordinated to the copper ion. During the course of this reaction, cesium bicarbonate is formed from cesium carbonate. The amido-copper (I) complex 4.2c undergoes an oxidative addition reaction with iodo-derivative forming a reaction intermediate 4.2d. This intermediate is ready for the C─N bond formation reaction, and the reductive elimination forms the desired rotaxane 4.2e and releases copper (I) iodide for the next catalytic cycle. Copper (I) acetate can also be used instead of copper (I) iodide.
Light and Color Production
Published in John A. Conkling, Christopher J. Mocella, Chemistry of Pyrotechnics, 2019
John A. Conkling, Christopher J. Mocella
As noted above, generation of the CuCl species produces an excellent blue flame, though that typically requires a chlorine source such as perchlorate, known to have environmental concerns as discussed previously. Furthermore, CuCl is an unstable species in flame and too high of a flame temperature can decompose the fleeting molecule, washing out the intended blue color and creating copper(II) oxide, which emits a red color. Research undertaken by Klapötke et al. suggested that a copper(I) iodide—CuI—could prove to be an equally suitable, or superior, blue-flame emitter (Klapötke, Rusan and Sabatini 2014). Whereas CuCl emits in the 435–480 nm blue region, CuI was suggested to emit around 460 nm. Copper(II) iodate—Cu(IO3)2—served as the oxidizer along with magnesium, guanidinium nitrate, and either urea or metallic copper to burn and generate the CuI species in the flame for emission. Performance was shown to be equal to, or even superior to, that of the CuCl emitting reference composition. Copper iodate is still prohibitively expensive for pyrotechnic compositions based on current market prices, but the research showing that successful chlorine-free copper-based blue-light emitters can be used in energetic materials is a significant advancement in the “greening” of pyrotechnics.
Properties of the Elements and Inorganic Compounds
Published in W. M. Haynes, David R. Lide, Thomas J. Bruno, CRC Handbook of Chemistry and Physics, 2016
W. M. Haynes, David R. Lide, Thomas J. Bruno
Copper(II) ferrocyanide Copper(II) ferrous sulfide Copper(I) fluoride Copper(II) fluoride Copper(II) fluoride dihydrate Copper(II) formate Copper(II) formate tetrahydrate Copper(II) gluconate Copper(II) hexafluoro-2,4-pentanedioate Copper(II) hexafluorosilicate tetrahydrate Copper(I) hydride Copper(II) hydroxide Copper(II) iodate Copper(II) iodate monohydrate Copper(I) iodide Copper(I) mercury iodide Copper(II) molybdate Copper(II) nitrate Copper(II) nitrate hexahydrate Copper(II) nitrate trihydrate Copper nitride Copper(II) oleate Copper(II) oxalate Copper(II) oxalate hemihydrate Copper(I) oxide Copper(II) oxide Copper(II) oxychloride hemiheptahydrate Copper(II) 2,4-pentanedioate Copper(II) perchlorate
Diaryl sulfides synthesis: copper catalysts in C–S bond formation
Published in Journal of Sulfur Chemistry, 2019
Lian Chen, Ali Noory Fajer, Zhanibek Yessimbekov, Mosstafa Kazemi, Masoud Mohammadi
Benzotriazole is an efficient ligand for the performance of coupling reactions in particular for the formation of carbon–sulfur bonds. In this respect, Verma and his co-workers exploited this ligand in the presence of CuI and DMSO for the coupling of various aryl thiols with aryl bromides to prepare diaryl sulfides in good to excellent yields (Scheme 3) [46]. Diaryl sulfides were prepared in good to excellent yields form the reaction of thiophenols derivatives with various aryl halides under CuBr-catalysis using 20 mol% 1,2,3,4-tetrahydro-8-hydroxy-quinoline and potassium carbonate in DMSO at 80°C (Scheme 4) [47]. The cleavage of the S–S bond in disulfides is one of the most common and best strategies for the synthesis of diaryl sulfides. In this respect, the use of 2-(ditert-butylphosphino)biphenyl in the presence of copper (I) iodide (CuI) and tetra n-butylammonium fluoride (TBAF) under solvent-free conditions is a suitable means for the cleavage of S-S bond in disulfides (Scheme 5) [48]. SanMartin and his co-workers have described the cross-coupling of a wide range of aryl thiols with activated aryl chlorides in an aqueous medium at 120°C and they found that ethylenediamine was an effective ligand and base for this purpose [49]. To carry out cross-coupling reactions, copper (I) iodide and water were used respectively as catalyst and solvent (Scheme 6).