CRYSTAL-STRUCTURE OF AN UNCOMPLEXED 25-CROWN-7 COMPRISING ONE 2,6-PYRIDINO AND 2 1,4-BENZO CONDENSATIONS

Citation
Me. Sobhia et al., CRYSTAL-STRUCTURE OF AN UNCOMPLEXED 25-CROWN-7 COMPRISING ONE 2,6-PYRIDINO AND 2 1,4-BENZO CONDENSATIONS, Journal of inclusion phenomena and molecular recognition in chemistry, 18(1), 1994, pp. 1-8
Citations number
21
Categorie Soggetti
Chemistry,Crystallography
ISSN journal
09230750
Volume
18
Issue
1
Year of publication
1994
Pages
1 - 8
Database
ISI
SICI code
0923-0750(1994)18:1<1:COAU2C>2.0.ZU;2-H
Abstract
Single crystal X-ray analysis of the uncomplexed crown macroring 1 is reported. Crystals are triclinic, P $($) over bar$$ 1, with a = 10.809 (1), b = 10.945(1), c = 10.256(1) Angstrom, alpha = 107.85(1), beta = 104.15(1), gamma = 87.27(1)degrees, D-c = 1.318 g cm(-3), Z = 2. Three torsion angles in the macrocycle take up gauche conformations in cont rast to the usual anti conformation. The crystal structure is stabiliz ed by intramolecular van der Waals forces and weak C-H...O and C-H...N hydrogen bond attractions. Stacking of pyridine rings is a noticeable packing feature in the crystal lattice.