Isomorphous crystal structures of chlorodi-acetyl-ene and iododi-acetyl-ene derivatives: simultaneous hydrogen and halogen bonds on carbon-yl.

ABSTRACT: The crystal structures of tert-butyl (5-chloro-penta-2,4-diyn-1-yl)carbamate, C10H12ClNO2 (II), and tert-butyl (5-iodo-penta-2,4-diyn-1-yl)carbamate, C10H12INO2 (IV), are isomorphous to previously reported structures and accordingly their mol-ecular and supra-molecular structures are similar. In the crystals of (II) and (IV), mol-ecules are linked into very similar two-dimensional wall organizations with anti-parallel carbamate groups involved in a combination of hydrogen and halogen bonds (bifurcated N-H?O=C and C?C-X?O=C inter-actions on the same carbonyl group). There is no long-range parallel stacking of diynes, so the topochemical polymerization of di-acetyl-ene is prevented. A Cambridge Structural Database search revealed that C?C-X?O=C contacts shorter than the sum of the van der Waals radii are scarce (only one structure for the C?C-Cl?O=C inter-action and 13 structures for the similar C?C-I?O=C inter-action).

SUBMITTER: Baillargeon P 

PROVIDER: S-EPMC5598843 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature