Quasi self-inclusion of a 1-D coordination polymer within a 2-D hydrogen-bonded grid: a chaperone effect

The one-dimensional (1-D) coordination polymer [Ni(bdc)(pico)2(H2O)2] (where bdc = terephthalate, pico = 4-picoline) is hosted within a two-dimensional (2-D) hydrogen-bonded grid [Ni(bdc)(pico)2(H2O)2]·(pyz) (where pyz = pyrazine). Both coordination polymers are comprised of the same components and differ only by their hydrogen-bonding patterns. The polymers of the 2-D grids engage in O–H···N hydrogen bonds to the included pyz. The grid contains rhombohedral cavities that lie along the crystallographic ac-plane. The grids self-assemble by C–H···π interactions involving the methyl group of pico and the aromatic ring of the bdc anion. The included polymer interacts with the 2-D grids via O–H···O hydrogen bonds involving coordinated water and the bdc anion

Metal–organic fireworks: MOFs as integrated structural scaffolds for pyrotechnic materials

A new approach to formulating pyrotechnic materials is presented whereby constituent ingredients are bound together in a solid-state lattice. This reduces the batch inconsistencies arising from the traditional approach of combining powders by ensuring the key ingredients are ‘mixed’ in appropriate quantities and are in intimate contact. Further benefits of these types of material are increased safety levels as well as simpler logistics, storage and manufacture. A systematic series of new frameworks comprising fuel and oxidiser agents (group 1 and 2 metal nodes & terephthalic acid derivatives as linkers) has been synthesised and structurally characterised. These new materials have been assessed for pyrotechnic effect by calorimetry and burn tests. Results indicate that these materials exhibit the desired pyrotechnic material properties and the effect can be correlated to the dimensionality of the structure. A new approach to formulating pyrotechnic materials is proposed whereby constituent ingredients are bound together in a solid-state lattice. A series of Metal–organic framework frameworks comprising fuel and oxidiser agents exhibits the desired properties of a pyrotechnic material and this effect is correlated to the dimensionality of the structure

Diversifying molecular and topological space via a supramolecular solid-state synthesis: a purely organic mok net sustained by hydrogen bonds

A three-dimensional hydrogen-bonded network based on a rare mok topology has been constructed using an organic molecule synthesized in the solid state. The molecule is obtained using a supramolecular protecting-group strategy that is applied to a solid-state [2+2] photodimerization. The photodimerization affords a novel head-to-head cyclobutane product. The cyclobutane possesses tetrahedrally disposed cis-hydrogen-bond donor (phenolic) and cis-hydrogen- bond acceptor (pyridyl) groups. The product self-assembles in the solid state to form a mok network that exhibits twofold interpenetration. The cyclobutane adopts different conformations to provide combinations of hydrogen-bond donor and acceptor sites to conform to the structural requirements of the mok net

Halogen-bonded zigzag molecular network based upon 1,2-diiodoperchlorobenzene and the photoproduct <i>rctt</i>-1,3-bis(pyridin-4-yl)-2,4-diphenylcyclobutane

The formation and crystal structure of a zigzag molecular network held together by I...N halogen bonds is reported. In particular, the halogen-bond donor is 1,2-diiodoperchlorobenzene (1,2-C6I2Cl4 ) while the acceptor is a head-to-tail photoproduct, namely rctt-1,3-bis(pyridin-4-yl)-2,4-diphenylcyclobutane ( ht -PP). In this co-crystal (1,2-C6I2Cl4 )·( ht-PP), the donor acts as a bent two-connected node while the acceptor behaves as a linear linker to form the extended solid. Neighbouring chains pack in a tongue-and-groove-like pattern that engage in various Cl...π interactions to both the phenyl and pyridyl rings resulting in a supramolecular two-dimensional sheet.</jats:p

Square network based upon the molecular salt of the tetraprotonated photoproduct <i>rtct</i>-tetrakis(pyridin-4-yl)cyclobutane and the sulfate anion

The formation and crystal structure of a hydrated molecular salt that results in a square network is reported. The crystalline solid is based upon the tetraprotonated photoproduct rtct-tetrakis(pyridin-4-yl)cyclobutane (4H- rtct -TPCB)4+ along with two sulfate anions (SO4 2−) and eight waters of hydration, namely, 4,4′,4′′,4′′′-(cyclobutane-1,2,3,4-tetrayl)tetrapyridinium bis(sulfate) octahydrate, C24H24N4 4+·2SO4 2−·8H2O. The fully protonated photoproduct acts as a four-connecting node within the square network by engaging in four charge-assisted N+—H...O hydrogen bonds to the sulfate anion. The observed hydrogen-bonding pattern in this square network is akin to T-silica, which is a metastable form of SiO2. The included water molecules and sulfate anions engage in numerous O—H...O hydrogen bonds to form various hydrogen-bonded ring structures.</jats:p