منابع مشابه
Aromatic rings act as hydrogen bond acceptors.
Simple energy calculations show that there is a significant interaction between a hydrogen bond donor (like the greater than NH group) and the centre of a benzene ring, which acts as a hydrogen bond acceptor. This interaction, which is about half as strong as a normal hydrogen bond, contributes approximately 3 kcal/mol (1 cal = 4.184 J) of stabilizing enthalpy and is expected to play a signific...
متن کاملLack of resonance interaction between the aromatic rings
Electronic spectra of a homo-molecular but inequivalent dimer ion, (C6H5OH)2 +, are measured by photodissociation spectroscopy. A broad band appeared in the 340–440 nm region is characteristic of the C ← X transition of a phenol ion chromophore, suggesting that the dimer ion consists of a phenol ion and a neutral phenol. No strong band is observed in the 450–1400 nm region, whereas other aromat...
متن کاملPacking of aromatic rings against tryptophan residues in proteins.
The geometry of the interaction of the aromatic side chains of phenylalanine (Phe), tyrosine (Tyr), tryptophan (Trp) and histidine (His) with the indole ring of Trp has been analyzed using the structures in the Protein Data Bank in order to understand the dependence of the packing behaviour on the size and chemical nature of the aromatic rings. The Phe ring prefers to interact either perpendicu...
متن کاملPoly(P-N-Chlorostyrenesulphonamide): A New and Efficient Chlorinating Agent for Aromatic Rings
Poly(p-N-chlorostyrenesulphonamide) synthesized via direct chlorination of poly[(p-styrene) sulphonamide], can be used for selective chlorination of aromatic compounds. Aromatic rings of the anisole, p-xylene, ethylbenzene and toluene are chlorinated with good yields. The polymer can be recovery, rechlorinated and reused several times.
متن کامل[3]Ferrocenophanes with the bisphosphanotetryl bridge: inorganic rings on the way to tetrylenes.
A series of [3]ferrocenophanes with functional P-E-P motifs (E = group 14 fragments) is reported. Out of these, the silicon compounds with the general formula Fe(C5H4PtBu)2SiXY (XY = Cl2, Br2, I2, H2, HCl) have been characterized by spectroscopic means and the bonding situation was analyzed using X-ray crystallography and quantum chemical calculations. Despite the two stereogenic phosphanyl cen...
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ژورنال
عنوان ژورنال: Pure and Applied Chemistry
سال: 1980
ISSN: 1365-3075,0033-4545
DOI: 10.1351/pac198052061443