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Methods have been developed for the synthesis of N-[2-(adamantan-2-yl)ethyl]-N′-R-ureas and -thioureas in 36–87% yields by the reaction of 2-(adamantan-2-yl)ethanamine with aromatic isocyanates and isothiocyanates. The displacement of the ethylene bridge from position 1 to position 2 of the adamantane fragment has been found to exert no significant effect on the logP values and melting points of the corresponding ureas. [ABSTRACT FROM AUTHOR]

The Chan–Lam reaction conditions were optimized for the synthesis of N-aryl derivatives of adamantane-containing amines. A number of adamantane-containing amines and diamines with different steric hindrances at the primary amino groups were reacted with p-tolylboronic acid under the optimized conditions [0.1 M solution of amine in MeCN, p-tolylboronic acid (2 equiv), DBU (2 equiv), copper(II) acetate (20 mol %), 25°C, 24 h]. The reactivity of the amines was found to strongly depend on their structure, and the maximum yield of the target products reached 74% from the monoamines and 66% from the diamines. [ABSTRACT FROM AUTHOR]

N-(Het)arylation of adamantane-containing amines with halonaphthalenes and haloquinolines catalyzed by either CuI or copper nanoparticles with an average size of 25 nm in the presence of 2-isobutyrylcyclohexanone, rac-BINOL, and l-proline as a ligand and Cs2CO3 as a base in DMSO at 110 °C was studied. The reactions proceed smoothly with 2-iodonaphthalene and 6-iodoquinoline, the possibility of successful reactions with 6- and 3-bromoquinolines was also shown. In the case of 1-bromonaphthalene, 5- and 8-bromoquinolines, only Pd-catalyzed amination can provide the high yields of the products. An alternative possibility of C(sp2)—N bond formation was studied employing the Chan—Lam reaction with of 2-naphthaleneboronic acid and pinacolates of 6- and 3-quinolineboronic acids. [ABSTRACT FROM AUTHOR]

Optically transparent polyimides (PIs) containing adamantane moieties in the structure of diamine unit were synthesized, and their properties were evaluated. The quantum-chemical calculations were also performed and revealed the energy difference (As) between the HOMO of the diamine and LUMO of the anhydride moieties for a large range of adamantane-containing PIs, which is usually associated with the optical absorption of organic compounds. It was found that the value of As does not always determine the optical properties of PI, especially in the case of PI with dianhydride moieties capable of strong intermolecular interactions. The presence of methyl groups at the core of adamantane-containing diamine leads to amorphization of the polymer, causing a positive effect on the optical properties of PI. [ABSTRACT FROM AUTHOR]

The N-heteroarylation of n-octylamine and adamantane-containing amines with 2-iodopyridine and 2-bromopyridine and its fluorinated derivatives under the catalysis of CuI and copper nanoparticles in DMSO in the presence of various ligands was studied. 2-Isobutyrylcyclohexanone was found to be the most efficient ligand in the reactions catalyzed by CuI. In the reactions catalyzed by copper nanoparticles, 2-isobutyrylcyclohexanone or l-proline turned to be most active. The yields of the reactions catalyzed by copper nanoparticles were better than or equal to those in the CuI-catalyzed processes. The possibility of nanocatalyst recycling was studied, and its reuse in 6 cycles without loss of activity was demonstrated. [ABSTRACT FROM AUTHOR]

N-Arylation of n-octylamine and adamantane-containing amines with iodobenzene and its deriva-tives has been performed in DMSO using copper(I) iodide and copper nanoparticles in the presence of various ligands as catalysts. In all cases, 2-isobutyrylcyclohexanone turned out to be the most efficient ligand, and higher yields of the arylation products were obtained in the presence of copper nanoparticles. The nanocatalyst can be recycled 9 times without significant loss of yield. [ABSTRACT FROM AUTHOR]

A comparative study of the catalytic efficiency of Pd(0) and Cu(I) complexes in the reactions of adamantanamines with fluoro- and trifluoromethyl-substituted 2-bromopyridines was carried out using previously optimized catalytic systems. It was shown that in the absence of steric hindrances in the starting compounds, the copper and palladium catalysts were comparable in efficiency. In some cases, the yields of the target N-heteroarylated compounds in the copper-catalyzed reactions were even higher, which can be explained by the formation of N,N-diheteroarylated by-products under palladium-catalyzed conditions. At the same time, ortho-fluorine- and ortho-trifluoromethyl-substituted 2-bromopyridines successfully react exclusively under palladium catalysis. [ABSTRACT FROM AUTHOR]

Alkylation of N-aryl and N-arylalkyl acetamides with hydroxy adamantane derivatives in trifluoroacetic acid was studied. The differentiating effect of trifluoroacetic acid on the regio-selectivity of adamantylation of o-alkyl-substituted acetanilides was established, leading to energetically more stable products of para-substitution with respect to the alkyl group (the content of para-alkyl isomers is 93–94%). This enabled the synthesis of adamantylaminoarenes in 83–99% yields and with 95–99% purity. [ABSTRACT FROM AUTHOR]

The catalytic efficiencies of palladium(0) and copper(I) complexes in the amination of 2-bromopyridine and its fluorine-containing derivatives with (1-adamantyl)methanamine and 2-(1-adamantyloxy)ethanamine were compared. Both types of catalytic systems were shown to be applicable for the preparation of the corresponding N-pyridyl derivatives from 3- and 5-fluoro- and 4-, 5-, and 6-trifluoromethyl-2-bromopyridines. DavePhos was found to be the most efficient ligand in the Pd(0)-catalyzed reactions; however, the reactions with 2-bromo-4-(trifluoromethyl)pyridine and 2-bromo-5-(trifluoromethyl)pyridine were accompanied by formation of a considerable amount of the diarylation product. The diarylation process was significantly suppressed in the presence of copper(I) complexes. [ABSTRACT FROM AUTHOR]