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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]

The reaction of adamantan-1-ol with lower alcohols (methanol, ethanol) in the presence of water and an equimolar amount of CuBr2 (with respect to adamantan-1-ol) at 220°C for 4 h gives adamantane in a high yield. (E)-(Prop-1-en-1-yl)adamantane was obtained in a high yield from adamantan-1-ol and isopropanol under similar conditions but in the absence of water. [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]

Metallothioneins (MTs) constitute an important family of metal binding proteins. Mollusk MTs, in particular, have been used as model systems to better understand the evolution of their metal binding features and functional adaptation. In the present study two recombinantly produced MTs, LgiMT1 and LgiMT2, and their de novo evolved γ domain, of the marine limpet Lottia gigantea, were analyzed by electronic spectroscopy and mass spectrometry. Both MT proteins, as well as their γ domains, exhibit a strong binding specificity for Cd(II), but not for Zn(II) or Cu(I). The LgiMTs' γ domain renders an MII4(SCys)10 cluster with an increased Cd stoichiometry (binding 4 instead of 3 Cd2+ ions), representing a novel structural element in the world of MTs, probably featuring an adamantane 3D structure. This cluster significantly improves the Cd(II)-binding performance of the full length proteins and thus contributes to the particularly high Cd coping capacity observed in free-living limpets. [ABSTRACT FROM AUTHOR]

Caged phosphines have unique structures and provide many advantageous properties that can be fine-tuned to develop efficient catalytic systems. Our research group recently introduced a highly water-soluble caged phosphine: PTABS (KapdiPhos), which is a derivatized form of triazaphosphaadamantane, and explored its applicability as a strongly π-accepting ligand in combination with metals such as Pd or Cu in a variety of cross-coupling reactions of biologically relevant halonucleosides as well as chloroheteroarenes. This account details our journey from ideation to the various catalytic applications of the ligands and eventually to its commercialization. 1 Introduction 2 Derivatization of PTA to PTABS and Its Applications 2.1 Nucleoside Modification 2.2 Heteroarene Modification 3 Conclusion 4 Summary and Future Outlook [ABSTRACT FROM AUTHOR]

Rapid development of the copper-catalyzed amination of aryl halides in the beginning of the 21st century, known as the Renaissance of the Ullmann chemistry, laid foundations for the use of this method as a powerful tool for the construction of the C(sp2)-N bond and became a rival of the Buchwald–Hartwig amination reaction. Various applications of this approach are well-documented in a number of comprehensive and more specialized reviews, and this overview in the form of a personal account of the Cu-catalyzed arylation and heteroarylation of the adamantane-containing amines, and di- and polyamines, covers a more specific area, showing the possibilities of the method and outlining general regularities, considering reagents structure, copper source and ligands, scope, and limitations. The material of the last decade is mainly considered, and recent data on the application of the unsupported copper nanoparticles and possibilities of the Chan-Lam reaction as an alternative to the use of aryl halides are also discussed. [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]

Reactions of adamantylazoles with nucleophiles (water, carbon monoxide, acetonitrile) in sulfuric acid were studied. New bifunctional adamantane derivatives containing one heterocyclic substituent and one hydroxyl or acetamide substituent were synthesized. The coordination compounds of copper(II) and zinc(II) with 1-adamantyl-1,2,4-triazole, 4-adamantylpyrazole, and 4-adamantyl-3,5-dimethylpyrazole were synthesized and structurally characterized. These complexes are first examples of coordination compounds of azolyladamantanes. [ABSTRACT FROM AUTHOR]

A simple imine clip‐and‐cleave concept has been developed for the selective hydroxylation of non‐activated CH bonds in aliphatic aldehydes with dioxygen through a copper complex. The synthetic protocol involves reaction of a substrate aldehyde with N,N‐diethyl‐ethylendiamine to give the corresponding imine, which is used as a bidentate donor ligand forming a copper(I) complex with [Cu(CH3CN)4][CF3SO3]. After exposure of the reaction mixture to dioxygen acidic cleavage and aqueous workup liberates the corresponding β‐hydroxylated aldehyde. The concept for the hydroxylation of trimethylacetaldehyde as well as adamantane and diamantane 1‐carbaldehydes was investigated and the corresponding β‐hydroxy aldehydes were obtained with high selectivities. The results of low temperature stopped‐flow measurements indicate the formation of a bis(μ‐oxido)dicopper complex as reactive intermediate. According to density functional theory (DFT, RI‐BLYP‐D3/def2‐TZVP(SDD)/ COSMO(CH2Cl2)//RI‐PBE‐D3/def2‐TZVP(SDD)) computations CH bonds suitably predisposed to the [Cu2O2]2+ core undergo hydroxylation in a concerted step with particularly low activation barriers, which explains the experimentally observed regioselectivities. Getting selective: A simple imine clip‐and‐cleave system has been developed for the selective hydroxylation of aldehydes with dioxygen through a copper complex. [ABSTRACT FROM AUTHOR]

Copper(I)-catalyzed arylation of 14 adamantane-containing amines with iodobenzene, 1-fluoro-4-iodobenzene, 1-iodo-4-(trifluoromethyl)benzene, and 1-iodo-4-methoxybenzene has been studied under the conditions optimized previously. The yields of the N-arylation products have been shown to depend in a complicated manner on the amine structure, steric environment of the amino group, and substituent nature in iodobenzene. [ABSTRACT FROM AUTHOR]

Three new complexes [Co(N3Py2)(H 2 O)](ClO 4 ) 2 1 , [Ni(N3Py2)(H 2 O)](ClO 4 ) 2 2 and [Cu(N3Py2)](ClO 4 ) 2 3 (N3Py2 is N , N ′-dimethyl- N -(2-(methyl(pyridin-2-ylmethyl)amino)ethyl)- N ′-(pyridin-2-ylmethyl)ethane-1,2-diamine) have been synthesized and characterized. Non-heme ligand N3Py2 have been prepared by Eschweiler-Clarke method and reported for the first time. Compounds 1 and 2 were characterized by single crystal X-ray structure analysis. The structure of 1 and 2 revealed that Co(II) cation in 1 and Ni(II) cation in 2 are bonded to the five nitrogen atoms of N3Py2 and a water molecule thus forming an octahedral motif [M(N3Py2)(H 2 O)] 2+ . For compound 3 , a square pyramidal geometry has been proposed based on the spectroscopic, elemental analysis and ESI-MS data. Compounds 1 – 3 were tested as catalysts in the oxidation of cumene and adamantane using m -CPBA. Comparative effect of counter anions on the product yields was observed when the perchlorates anions of 1 – 3 were replaced with tetraphenylborates to give compounds 1a – 3a . The turnover numbers of alcohol over ketone product increased in order of catalysts, 1 ( 1a ) > 2 ( 2a ) > 3 ( 3a ). [ABSTRACT FROM AUTHOR]

Five pentacoordinate copper(II) complexes with 2-acetylpyridine or di(2-pyridyl) ketone 1-adamantoyl hydrazone ligands (Adpy and Addpy, respectively) of the formulae [CuCl2(Adpy)] ( 1), [Cu2(μ-Cl)2(Adpy-H)2] ( 2), [Cu(NCS)2(Adpy)] ( 3), [Cu2(μ-Cl)2(Addpy-H)2] ( 4), and [Cu2(NCS)2(μ-Addpy-H)2] ( 5) were synthesized and characterized by spectral, electrochemical, and X-ray structural analysis. Flow cytometry and morphological analysis confirmed that the copper(II) complexes 2 and 5 induced accumulation of a sub-G1 phase population, and fluorescence microscopy indicated the presence of large cells in apoptosis. The interaction of the copper(II) complexes with calf thymus DNA (CT-DNA) was monitored by changes in their UV/Vis spectra. The observed intrinsic binding constants for 2 and 5 ( Kb = 1.77 × 106 and 3.58 × 106 M-1, respectively) together with ethidium displacement fluorescence experiments indicate intercalative binding. Complexes 2 and 5 showed nuclease activity against pUC19 plasmid DNA. [ABSTRACT FROM AUTHOR]

A hydroxamic acid of a new type, N-hydroxyhomoazaadamantanone (HL), has been synthesized, combining several structure peculiarities: cage skeleton, heterocyclicity, and rigidly fixedcis-orientation of the oxygens of the hydroxamate fragment of the molecule. Complexes of HL with dioxo-molybdenum(VI) ((MoO2LC2H5OH)2O) and copper(II) (CuL2) have been synthesized. All compounds were characterized by IR and1H NMR spectroscopy. X-ray structural analyses of N-hydroxyhomoazaadamantanone hydrochloride and the coordination compounds have been carried out. [ABSTRACT FROM AUTHOR]

New triazole-based CuII metal-organic frameworks, [Cu(tr2ad)(SO4)] ·3H2O ( 1), [Cu3(tr2ad)4(H2O)2(SO4)2]SO4 ·28H2O ( 2), [Cu3(tr2ad)4(H2O)4](SiF6)3 ·16H2O ( 3), constructed utilizing a rigid adamantane scaffold, tr2ad = 1,3-bis(1,2,4-triazol-4-yl)adamantane, were prepared hydrothermally, and their crystal structures were determined. The structure of 1 is built up from straight chains of corner-sharing CuN4O2 octahedra supported by short μ2-tr (tr = 1,2,4-triazole) and μ2-SO42- bridges. The tetradentate character of tr2ad results in the formation of layers. The 2D structures of 2 and 3 consist of discrete secondary building blocks [Cu3(μ2- N1, N2-tr)6] with triple [-N-N-] triazole links between the adjacent Cu centers [the Cu-(tr)-Cu separations are 3.806 and 3.756 Å for 2 and 3, respectively]. The distorted octahedral N4O2 environment of the peripheral Cu atoms is completed by water molecules and/or terminal sulfate anions. The linear magnetic clusters, which act as nodes, are joined together at average distances of 11.2 and 15.0-15.6 Å into square-grid-like networks that exploit the double-bridging μ3- and μ4-bis(triazole) modules. Uncoordinated counteranions and crystal water molecules fill the interlayer space and channels in the complexes and form extensive H-bonding patterns. The exchange integrals J1 = 9.8 and J2 ≈ 0 cm-1 for the interaction J1( Ŝ1 Ŝ2 + Ŝ2 Ŝ3) + J2 Ŝ1 Ŝ3 were determined for 3 from magnetic susceptibility data and reproduced by a broken-symmetry DFT calculation. The spin Hamiltonian parameters of 3 were found from high-field electron paramagnetic resonance (EPR) spectra. [ABSTRACT FROM AUTHOR]

Abstract: Two new structurally characterized coordination polymers containing the P4(NR)6 ligand system are described. A convenient one-pot synthesis of P4(NR)6 (R=benzyl) via reaction of lithiated primary amine with phosphorus trichloride demonstrates an expanded scope for the preparation of this adamantane-type structure. Reactions of P4(NR)6 (R=Et, Bn) with cuprous iodide yield different products due to the differences in steric demands of the ligands. [ABSTRACT FROM AUTHOR]

The self-assembly of the flexible tetrahedral linker tetrakis[4-(carboxyphenyl)oxamethyl]methane acid with various transition metals (Cu, Co, and Mg) results in a 2D layered structure and 3D frameworks with PtS and adamantanoid topology. The PtS net exhibits permanent porosity, as confirmed by BET and gas adsorption experiments. [ABSTRACT FROM AUTHOR]

Abstract  The formation from aqueous solution of networks containing piperazinium hydrochlorides with copper(I) chloride is described. Four new X-ray crystal structures are reported: (H2Pip)[Cu2Cl4] (two isomeric phases: 1A and 1B), (H2MePip)[Cu3Cl5] (2), and (H2Me2Pip)[Cu4Cl6] (3) (Pip = piperazine, MePip = N-methylpiperazine, Me2Pip = N,N′-dimethylpiperazine. In 1A (P-1, a = 6.3141(2), b = 6.8248(2), c = 6.9067(2), α = 90.707(2), β = 110.748(2), γ = 110.799(2), V = 256.918(13), Z = 2) corner-sharing Cu2Cl2 rhomboid dimers form infinite chains running parallel to the a-axis. In 1B (Pbcn, a = 9.9442(6), b = 8.0622(5), c = 13.1301(7), V = 1052.67(11), Z = 8) the Cu2Cl2 dimers are linked by μ-Cl into Cu6Cl8 rings which form hexagonally tiled sheets running parallel to the a,b-plane. In 2 (P-1, a = 8.0815(7), b = 9.6584(9), c = 9.7900(8), α = 70.231(4), β = 77.180(4), γ = 70.587(4), V = 673.05(10), Z = 2) alternating Cu3Cl3 and Cu4Cl4 rings are fused to form ribbons that run parallel to the a-axis. Copper-copper interactions are present. In 3 (C2/c, a = 17.4026(6), b = 10.5295(4), c = 11.7501(8), β = 131.5490(10), V = 1611.35(14), Z = 8) relatively long Cu···Cl interactions connect Cu4Cl6 “adamantane” units into chains running parallel to the c-axis. In all cases the piperazinium ions are independent from the chlorocuprate structures, but they do show N–H···Cl interactions. Index Abstract  The synthesis and network structures of four piperazinium hydrochlorides with copper(I) chloride are presented. [ABSTRACT FROM AUTHOR]

Two new bulky ligands, N-(1-adamantyl)-3,5-tBu2-salicylaldimine (1), and N-(2-adamantyl)-3,5-tBu2-salicylaldimine (2), and their copper bis-chelate complexes, 3 and 4, have been prepared and their analytical, spectroscopic and magnetic properties, chemical and electrochemical redox reactivity are described. EPR and UV/Vis results [higher g∥/A∥, lower energy λ (nm)] for 3 and 4 suggest a distorted square planar geometry with a higher degree of distortion for 3 than for 4. Chemical oxidation of 1–4 by ACN, on the basis of their EPR and UV/Vis spectra results in the formation of the free 1+, 2+ phenoxyl and Cu(II)-phenoxyl radicals complexes [g = 2.0065 (3+), 2.0099 (4+) and λmax at ca. 430 and 720 nm]. Electrochemical studies have shown that the complexes possess ligand- and copper(II)-centered quasi-reversible and irreversible responses and the more distorted complex 3, having the bulkier 1-adamantyl on the imine nitrogen, was reduced at a more negative potential than the less distorted complex 4. [Copyright &y& Elsevier]

The new coordination polymers (CPs) [Zn(tr2ad)Cl2]n, {[Cu(tr2ad)Cl]Cl∙4H2O}n, [Cd2(tr2ad)Cl4]n, {[Cu(tr2ad)(NO3)](NO3)}n and {[Cd(tr2ad)(NO3)](NO3)∙H2O}n were obtained in the form of air- and moisture-stable microcrystalline powders by the solvothermal reactions of zinc(II), copper(II) and cadmium(II) chlorides or nitrates with the ligand 1,3-bis(1,2,4-triazol-4-yl)adamantane (tr2ad). Investigation of the thermal behaviour assessed the thermal stability of these CPs, with [Cd2(tr2ad)Cl4]n starting to decompose only around 365 °C. As retrieved by powder X-ray diffraction, while [Zn(tr2ad)Cl2]n features 1-D chains along which the metal centre shows a tetrahedral geometry and the spacer is exo-bidentate, the other CPs contain 2-D double-layers in which the metal ions possess an octahedral stereochemistry and the linker is exo-tetradentate. A comparative structural analysis involving known coordination compounds containing the tr2ad ligand enabled us to disclose (i) the versatility of the ligand, as far as the coordination modes are concerned; (ii) the variability in crystal structure dimensionality, ranging from 1-D to 3-D; (iii) the fact that, to the best of our knowledge, [Zn(tr2ad)Cl2]n is the first ZnII-based CP containing the tr2ad spacer. [ABSTRACT FROM AUTHOR]