Crown ethers as pre-organised exo-receptors in the divergent recognition of alpha,omega-diiodoperfluoroalkanes

Author(s): Navarrini, W; Metrangolo, P; Pilati, T; Resnati, G.


Volume: 24 Issue: 10 Pages: 777-780

DOI: 10.1039/b002247k Published: 2000


Both the nitrogen atoms of Kryptofix(R) 2.2. 1 act as electron-donors to the iodine atoms of alpha,omega-diiodoperfluoroalkanes 2a,b giving rise to infinite 1D chains 3a,b as white crystalline solids which are stable in air at room temperature. The structural features of these non-covalent co-polymers have been studied using various techniques (IR, H-1 NMR, F-19 NMR, X-ray diffraction) and it has been established that when Kryptofix 2.2. is halogen bonded to iodides 2, it adopts the same conformation as when in the pure form, namely the exo-exo topology. The co-existence of halogen-bonding and hydrogen-bonding in supramolecular architectures 3 suggests pre-organisation of the interacting partners as a new strategy in the rational design of divergent self-assembly processes.!divAbstract

Infrared and Raman analyses of the halogen-bonded non-covalent adducts formed by alpha,omega-diiodoperfluoroalkanes with DABCO and other electron donors

Author(s): Messina, MT; Metrangolo, P; Navarrini, W; Radice, S; Resnati, G; Zerbi, G.


Volume: 524 Pages: 87-94

DOI: 10.1016/S0022-2860(99)00445-7 Published: JUN 13 2000


An attractive intermolecular interaction which has been called “halogen bonding” exists between the nitrogen, sulfur, or oxygen atoms present in HC motifs and the iodine atom of PFC residues. The “halogen bonding” is strong enough to overcome the low affinity existing between PFC and HC compounds, driving their self-assembly into supramolecular architectures. The non-covalent co-polymer formed by 1,2-diiodotetrafluoroethane with diazabicyclooctane has been prepared and characterised by FT-IR and -Raman spectroscopies. We propose the changes shown by the vibrational spectra of single PFC and HC components when involved in halogen bonded co-polymers as diagnostic probes of the interaction and as tools to rank the electron-donor ability of differently heteroatom substituted hydrocarbons.

COD ID: 7051307

From Repository: Crystallography Open Database.

Author(s): Navarrini, Walter; Metrangolo, Pierangelo; Pilati, Tullio; Resnati, Giuseppe

Source: Crystallography Open Database Source URL: Published Year: 2000