1241387-02-9Relevant academic research and scientific papers
Synthetic and structural studies of l-halo-8-(alkylchalcogeno)naphthalene derivatives
Knight, Fergus R.,Fuller, Amy L.,Buehl, Michael,Slawin, Alexandra M. Z.,Woollins, J. Derek
experimental part, p. 7605 - 7616 (2010/08/20)
A series of eight l-halo-8-(alkylchalcogeno)naphthalene derivatives (1-8; halogen = Br, I; alkylchalcogen = SEt, SPh, SePh, TePh) containing a halogen and a chalcogen atom occupying the peri positions have been prepared and fully characterised by using X-ray crystallography, multinuclear NMR spectroscopy, IR spectroscopy and MS. Naphthalene distortion due to non-covalent substituent interactions was studied as a function of the bulk of the interacting chalcogen atoms and the size and nature of the alkyl group attached to them. X-ray data for 1, 2, 4 and 5-8 were compared. Molecular structures were analysed in terms of naphthalene ring torsions, peri-atom displacement, splay angle magnitude, X-E interactions, aromatic ring orientations and quasi-linear X-E-C arrangements. A general increase in the X-E distance was observed for molecules that contain bulkier atoms at the peri positions. The I-S distance of 4 is comparable with the I-Te distance of 8, and is ascribed to a stronger lone pair-lone pair repulsion due to the presence of an axial S(naphthyl) ring conformation. Density functional theory (B3LYP) calculations performed on 5-8 revealed Wiberg bond index values of 0.05-0.08, which indicate minor interactions taking place between the non-bonded atoms in these compounds.
Synthetic and structural studies of 1, 8-chalcogen naphthalene derivatives
Knight, Fergus R.,Fuller, Amy L.,Buehl, Michael,Slawin, Alexandra M. Z.,Woollins, J. Derek
body text, p. 7503 - 7516 (2010/08/20)
Four novel 1,8-disubstituted naphthalene derivatives 4-7 that contain chalcogen atoms occupying the peri positions have been prepared and fully characterised by using X-ray crystallography, multinuclear NMR spectroscopy, IR spectroscopy and MS. Molecular distortion due to noncovalent substituent interactions was studied as a function of the bulk of the interacting chalcogen atoms and the size and nature of the alkyl group attached to them. X-ray data for 4-7 was compared to the series of known 1, 8-bis(phenylchalcogeno) naphthalenes 1-3, which were themselves prepared from novel synthetic routes. A general increase in the E-E' distance was ob-served for molecules containing bulkier atoms at the peri positions. The decreased S...S distance from phenyl-1 and ethyl-4 analogues is ascribed to a weaker chalcogen lone pair-lone pair repulsion acting in the ethyl analogue due to the presence of two equatorial S(naphthyl) ring conformations. Two novel pen-substituted naphthalene sulfoxides of 1, Nap(O=SPh)(SPh) 8 and Nap(O=SPh)2 9, which contain different valence states of sulfur, were pre-pared and fully characterised by using X-ray crystallography and multinuclear NMR spectroscopy, IR spectroscopy and MS. Molecular structures were analysed by using naphthalene ring torsions, peri-atom displacement, splay angle magnitude, S...S interactions, aromatic ring orientations and quasi-linear O=S...S arrangements. The axial S(naphthyl) rings in 8 and 9 are unfavourable for S-S contacts due to stronger chalcogen lone pair-lone pair repulsion. Although quasi-linear O=S...S alignments suggest attractive interaction is conceivable, analysis of the B3LYP wavefunctions affords no evidence for direct bonding interactions between the S atoms.
