ABSTRACT
New, halogen-bonded fluorinated mesogens are reported; the expected microphase separation associated with perfluoroalkyl chains is surprisingly absent in the mesophase.
ABSTRACT
Two homologues of supramolecular Borromean rings were obtained based on the halogen-bonding-driven self-assembly of iodide ions with telechelic diiodoperfluoroalkanes.
ABSTRACT
The halogen bonding driven self-assembly of 1,8-diiodoperfluorooctane and N,N,N',N'-tetramethyl-p-phenylenediamine induces the formation of a chiral and enantiopure co-crystal wherein the fluorinated chains adopt an unusual gauche arrangement.
ABSTRACT
The halogen bonding and the pi...pi stacking interactions induce the noncovalent self-assembly of modules into photoreactive supramolecular architecture. The pi...pi interaction pre-organizes the template, and the halogen bonding aligns the olefins to conform to the topochemical principle for photoreaction. The UV irradiation of the crystal resulted in a cyclization product with quantitative yield and stereospecificity.
ABSTRACT
The N.Br halogen bonding drives the self-assembly of 1,4-dibromotetrafluorobenzene (1 a) and its 1,3 or 1,2 analogues (1 b,c, respectively) with dipyridyl derivatives 2 a,b. The isomeric supramolecular architectures 3 a-f are obtained as cocrystals that are stable in the air at room temperature. The solid-state features of these 1D infinite chains 3 have been fully characterized by single-crystal X-ray, Raman, and IR analyses. The occurrence of N.Br halogen bonding in solution has been detected with (19)F NMR spectroscopy. The N.Br halogen bonding is highly selective and directional and the geometry of the single strands of noncovalent copolymers 3 is programmed by the geometry of halogen-bonding donor and acceptor sites on the starting modules. The composition and topology of the instructed networks can be predicted with great accuracy. Experiments of competitive cocrystal formation established the strength of the N.Br interaction relative to other halogen bondings and the ability of different modules 1 to be involved in site-selective supramolecular syntheses.