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Exo conformers of N ‐(pyridin‐2‐yl)‐ and N ‐(pyridin‐3‐yl)norbornene‐5,6‐dicarboximide crystals
Author(s) -
VazquezVuelvas Oscar F.,
HernándezMadrigal Julia V.,
PinedaContreras Armando,
HernándezOrtega Simón,
ReyesMartínez Reyna,
MoralesMorales David
Publication year - 2015
Publication title -
acta crystallographica section c
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.304
H-Index - 17
ISSN - 2053-2296
DOI - 10.1107/s2053229615001886
Subject(s) - norbornene , chemistry , molecule , pyridine , stereochemistry , conformational isomerism , crystallography , ring (chemistry) , intermolecular force , crystal structure , methylene bridge , methylene , medicinal chemistry , organic chemistry , monomer , polymer
Two isomeric pyridine‐substituted norbornenedicarboximide derivatives, namely N ‐(pyridin‐2‐yl)‐ exo ‐norbornene‐5,6‐dicarboximide, (I), and N ‐(pyridin‐3‐yl)‐ exo ‐norbornene‐5,6‐dicarboximide, (II), both C 14 H 12 N 2 O 4 , have been crystallized and their structures unequivocally determined by single‐crystal X‐ray diffraction. The molecules consist of norbornene moieties fused to a dicarboximide ring substituted at the N atom by either pyridin‐2‐yl or pyridin‐3‐yl in an anti configuration with respect to the double bond, thus affording exo isomers. In both compounds, the asymmetric unit consists of two independent molecules ( Z ′ = 2). In compound (I), the pyridine rings of the two independent molecules adopt different conformations, i.e. syn and anti , with respect to the methylene bridge. The intermolecular contacts of (I) are dominated by C—H...O interactions. In contrast, in compound (II), the pyridine rings of both molecules have an anti conformation and the two independent molecules are linked by carbonyl–carbonyl interactions, as well as by C—H...O and C—H...N contacts.