1,3,5,7-Tetrakis(tetrazol-5-yl)-adamantane: the smallest tetrahedral tetrazole-functionalized ligand and its complexes formed by reaction with anhydrous M(ii)Cl₂(M = Mn, Cu, Zn, Cd)

Abstract

·62 ·8}, gis or gismondine underlying net, where the role of the tetrahedral nodes is served by the coordination bonded clusters and the adamantane moiety. 3 (P2 1 /n) has a porous structure composed of coordination bonded layers with a (4·8 2 ) fes topology joined via trans-{Zn- The high number of donor functions endows the tetrazolate function with a capability to sustain unusually high number of coordination bonded arrangements ( patterns) 7 compared to other azolates. In the case of simple rigid ligands it is a prerequisite for assembly of a highly symmetric framework, with a † Dedicated to Prof. Marius Andruh on the occasion of his 60th birthday. View Article OnlineView Journal | View Issue significant probability of isomerism. Indeed, the linear 1,4-benzeneditetrazole (H 2 BDT) 8 and flat triangular 1,3,5-benzene- hedral' tetrazolates and involving chloride anions as coligands, serve as an interesting example of variability of coordination-bonded cluster geometry and size due to involvement of short halido bridges. 16,20 It was conjectured that mixed tetrazolato/halido coordination polymers constitute an interesting compound class with 'scalable' multinuclear clusters, 20 which are interesting either as robust SBUs or possibly as functional magnetic units. In this contribution we probed the practically unexplored 1,3,5,7-tetrakis(tetrazol-5yl)adamantane ligand (H 4 L) as a building block for coordination polymers using conditions favoring formation of tetrazolato/halido clusters (Scheme 1). This ligand in anionic form has one of the highest density of donor sites achievable for a 'tetrahedral' ligand, which is a prerequisite for rich coordination and structural chemistry of derived coordination-bonded frameworks. Results and discussion The ligandUniversal rigid molecular platforms with tetrahedral symmetry are typically limited to tetraphenylmethane (including 9,9′-spirobifluorene) and adamantane, as well as their phenyl augmented and heteroatom-substituted analogues.14 Adamantane is the smallest tetrahedral platform next only to quaternary carbon, while the latter has inherent steric limitations. Adamantane is widely used for the synthesis of organic polymers (recently with an emphasis on porous organic polymers and covalent organic frameworks), 22 dendrimers, 23 and molecular entities for supramolecular synthesis 24 and nanotechnology. 25Compared to tetraphenylmethane, whose modification is standard and facile, the chemistry of adamantanes is peculiar, at times cumbersome, but offering synthetic opportunities as well. For example adamantane could be selectively brominated in bridgehead positions to afford mono-to tetra-substituted adamantanes in high yields. 26 However, 1,3,5,7-tetrabromoadamantane is the most chemically inert entity in the row and the substitution of halogens via the S N1 mechanism demands harsh conditions. It was not only until the recent paper of Lee et al.,27 in which photochemical cyanodebromination of 1,3,5,7-tetrabromoadamantane was described that a facile route to various tetra...

Dimetallic Palladium‐NHC Complexes: Synthesis, Characterization, and Catalytic Application for Direct C−H Arylation Reaction of Heteroaromatics with Aryl Chlorides

“…[33] Absorption corrections were performed using the SADABS program. These results were in good agreement with the volume occupied by 24 DMF molecules in the unit cell (127 Å 3 and 40 electrons per DMF [37] ). [35] All non-H atoms were refined anisotropically.…”

Structural Diversity Ranging from Oligonuclear Complexes to 1‐D and 2‐D Coordination Polymers Generated by Tetrasubstituted Adamantane and Spirobifluorene Derivatives

“…Several network topologies mimicking basic inorganic structural prototypes have been constructed from tetrahedral nodes: diamondoid (dia), platinum sulfide (pts), fluorite (flu), SrAl 2 (sra), etc . Tetradentate tectons built around a tetrahedral core (adamantane, methane,[3m], [3n], [3o], [3p], [3q], silane,[4b], [4m], germane[5a]) are endowed with the specific orientation of the donor groups toward the corners of a tetrahedron, resulting in 3‐D networks. However, 2‐D systems built on tetrahedral shaped linkers have been also described.…”

“…However, 2‐D systems built on tetrahedral shaped linkers have been also described. [3j], [5c], We have, recently, emphasized the role played by the coordination preference of the metal center, along with the tetrahedral organic linker′s symmetry, in assembling in a 3‐D framework featuring a PtS topology, or a 2‐D grid‐like coordination polymer. [6d]…”

1,3-Bis(1,2,4-triazol-1-yl)adamantane

“…They find use in polymer synthesis [8], the design of nanostructured materials [9,10], ionic liquids [11], and coordination chemistry [12,13]. In addition, arrangement of azoles around a rigid linker makes azolyladamantanes perfect auxiliary ligands for metal-organic framework design; however, only a few examples of such ligands (with 4H-1,2,4-triazolyl and tetrazolyl moieties) have been reported [14][15][16][17][18]. Claramunt et al reported the monoadamantylation of a number of azoles by their reaction with 1-bromoadamantane at 120-200 • C [4,[19][20][21][22].…”