0000000001300200
AUTHOR
Tullio Pilati
Dissecting the packing forces in mixed perfluorocarbon/aromatic co-crystals
We carried out a systematic evaluation of the packing forces in co-crystals featuring monoiodo- and diiodo-perfluoroalkanes and 1,2,4-oxadiazoles through single crystal X-ray diffraction and theoretical analysis. The molecules assemble via a combination of halogen bonding and specific dispersive interactions involving the perfluorinated units. We quantitatively elucidated the nature and strength of such interactions through solid-state calculations and Hirshfeld surface analysis. One of the co-crystals, formed by two monoiodoperfluorodecane molecules, the longest perfluorinated chain ever solved at the atomic level, allowed us to fully highlight the role of fluorous interactions.
Halogen bond directionality translates tecton geometry into self-assembled architecture geometry
The structures of halogen-bonded infinite chains involving two diiodoperfluoroalkanes and a bent bis(pyrid-4′-yl)oxadiazole show that the geometry of the pyridyl pendant rings is translated into the angle between the formed halogen bonds.
Superfluorinated ionic liquid crystals based on supramolecular, halogen-bonded anions
Unconventional ionic liquid crystals in which the liquid crystallinity is enabled by halogen-bonded supramolecular anions [CnF2 n+1-I⋯I⋯I-CnF2 n+1]- are reported. The material system is unique in many ways, demonstrating for the first time 1) ionic, halogen-bonded liquid crystals, and 2) imidazolium-based ionic liquid crystals in which the occurrence of liquid crystallinity is not driven by the alkyl chains of the cation. Out of the ordinary: The high directionality of halogen bonds and the fluorophobic effect were exploited in the design and synthesis of a new family of unconventional superfluorinated ionic liquid crystals. The liquid crystallinity of the system is driven by halogen-bonded…
Coordination networks incorporating halogen-bond donor sites and azobenzene groups
Two Zn coordination networks, {[Zn(1)(Py)2]2(2-propanol)}n (3) and {[Zn(1)2(Bipy)2](DMF)2}n (4), incorporating halogen-bond (XB) donor sites and azobenzene groups have been synthesized and fully characterized. Obtaining 3 and 4 confirms that it is possible to use a ligand wherein its coordination bond acceptor sites and XB donor sites are on the same molecular scaffold (i.e., an aromatic ring) without interfering with each other. We demonstrate that XBs play a fundamental role in the architectures and properties of the obtained coordination networks. In 3, XBs promote the formation of 2D supramolecular layers, which, by overlapping each other, allow the incorporation of 2-propanol as a gues…
Nonporous Organic Solids Capable of Dynamically Resolving Mixtures of Diiodoperfluoroalkanes
Halogen bonding has increasingly facilitated the assembly of diverse host-guest solids. Here, we show that a well-known class of organic salts, bis(trimethylammonium) alkane diiodides, can reversibly encapsulate α,ω-diiodoperfluoroalkanes (DIPFAs) through intermolecular interactions between the host's I – anions and the guest's terminal iodine substituents. The process is highly selective for the fluorocarbon that forms an I – ···I(CF 2 ) m I···I – superanion that is matched in length to the chosen dication. DIPFAs that are 2 to 12 carbons in length (common industrial intermediates) can thereby be isolated from mixtures by means of crystallization from solution upon addition of the dissolv…
Photoalignment and Surface-Relief-Grating Formation are Efficiently Combined in Low-Molecular-Weight Halogen-Bonded Complexes
It is demonstrated that halogen bonding can be used to construct low-molecular-weight supramolecular complexes with unique light-responsive properties. In particular, halogen bonding drives the formation of a photoresponsive liquid-crystalline complex between a non-mesogenic halogen bond-donor molecule incorporating an azo group, and a non-mesogenic alkoxystilbazole moiety, acting as a halogen bond-acceptor. Upon irradiation with polarized light, the complex exhibits a high degree of photoinduced anisotropy (order parameter of molecular alignment > 0.5). Moreover, efficient photoinduced surface-relief-grating (SRG) formation occurs upon irradiation with a light interference pattern, with…
Lower rim arylation of calix[n]arenes with extended perfluorinated domains
Abstract Exhaustive O-arylation of p-tert -butylcalix[ n ]arenes 2 ( n = 4–8) with an excess of 3-pentadecafluoroheptyl-5-pentafluorophenyl-1,2,4-oxadiazole 3 and K 2 CO 3 in refluxing acetonitrile provides an easy entry to a new family of perfluorinated calix[ n ]arenes 1 . The cyclic tetramer furnishes a mixture of cone , partial cone , and 1,2-alternate conformers, while the larger macrocycles afford single products. The structures of all new compounds are substantiated by NMR techniques and MALDI-TOF mass spectral data. Single-crystal X-ray diffraction studies on the pentamer derivative 1b reveal a distorted cone-in conformation of the calixarene cup.
Dimensional encapsulation of I− I 2 I− in an organic salt crystal matrix
Bis(trimethylammonium)hexane diiodide encapsulates iodine from solution and through a gas/solid reaction yielding in a predictable and controllable manner the selective formation of the rare polyiodide species I(-)...I-I...I(-), which matches in length to the chosen dication.
Supramolecular control of liquid crystals by doping with halogen-bonding dyes
Introducing photochromic or polymeric dopants into nematic liquid crystals is a well-established method to create stimuli-responsive photonic materials with the ability to "control light with light". Herein, we demonstrate a new material design concept by showing that specific supramolecular interactions between the host liquid crystal and the guest dopants enhance the optical performance of the doped liquid crystals. By varying the type and strength of the dopant-host interaction, the phase-transition temperature, the order parameter of the guest molecules, and the diffraction signal in response to interference irradiation, can be accurately engineered. Our concept points out the potential…
Azobenzene-based difunctional halogen-bond donor: Towards the engineering of photoresponsive co-crystals
Halogen bonding is emerging as a powerful non-covalent interaction in the context of supramolecular photoresponsive materials design, particularly due to its high directionality. In order to obtain further insight into the solid-state features of halogen-bonded photoactive molecules, three halogen-bonded co-crystals containing an azobenzene-based difunctional halogen-bond donor molecule, (E)-bis(4-iodo-2,3,5,6-tetrafluorophenyl)diazene, C12F8I2N2, have been synthesized and structurally characterized by single-crystal X-ray diffraction. The crystal structure of the non-iodinated homologue (E)-bis(2,3,5,6-tetrafluorophenyl)diazene, C12H2F8N2, is also reported. It is demonstrated that the stud…
CCDC 1445294: Experimental Crystal Structure Determination
Related Article: Francisco Fernandez-Palacio, Marco Saccone, Arri Priimagi, Giancarlo Terraneo, Tullio Pilati, Pierangelo Metrangolo, Giuseppe Resnati|2016|CrystEngComm|18|2251|doi:10.1039/C6CE00059B
CCDC 1535157: Experimental Crystal Structure Determination
Related Article: Jaana Vapaavuori, Antti Siiskonen, Valentina Dichiarante, Alessandra Forni, Marco Saccone, Tullio Pilati, Christian Pellerin, Atsushi Shishido, Pierangelo Metrangolo, Arri Priimagi|2017|RSC Advances|7|40237|doi:10.1039/C7RA06397K
CCDC 1446403: Experimental Crystal Structure Determination
Related Article: Gabriella Cavallo, Giancarlo Terraneo, Alessandro Monfredini, Marco Saccone, Arri Priimagi, Tullio Pilati, Giuseppe Resnati, Pierangelo Metrangolo, Duncan W. Bruce|2016|Angew.Chem.,Int.Ed.|55|6300|doi:10.1002/anie.201601278
CCDC 883070: Experimental Crystal Structure Determination
Related Article: Arri Priimagi, Marco Saccone, Gabriella Cavallo, Atsushi Shishido, Tullio Pilati, Pierangelo Metrangolo and Giuseppe Resnati|2012|Adv.Mater.|24|OP345|doi:10.1002/adma.201204060
CCDC 1445292: Experimental Crystal Structure Determination
Related Article: Francisco Fernandez-Palacio, Marco Saccone, Arri Priimagi, Giancarlo Terraneo, Tullio Pilati, Pierangelo Metrangolo, Giuseppe Resnati|2016|CrystEngComm|18|2251|doi:10.1039/C6CE00059B
CCDC 1445293: Experimental Crystal Structure Determination
Related Article: Francisco Fernandez-Palacio, Marco Saccone, Arri Priimagi, Giancarlo Terraneo, Tullio Pilati, Pierangelo Metrangolo, Giuseppe Resnati|2016|CrystEngComm|18|2251|doi:10.1039/C6CE00059B
CCDC 2077920: Experimental Crystal Structure Determination
Related Article: Marco Saccone, Andrea Pace, Ivana Pibiri, Gabriella Cavallo, Pierangelo Metrangolo, Tullio Pilati, Giuseppe Resnati, Giancarlo Terraneo|2021|CrystEngComm|23|7324|doi:10.1039/D1CE01001H