Die Kristall- und Molekülstruktur eines neuratigen phthalocyaninähnlichen Borkomplexes

Abstract

The crystal structure of the phthalocyanine-like boron complex 15c-chloro-triisoindolo[1,2,3−cd ∶ 1′,2′,3′−gh ∶ 1″,2″,3″−kl]-[2,3a,5,6a,8,9a,9b]-hexaazaboraphenalene (C₈H₄N₂)₃BCl has been determined from single crystal diffractometer data. The space group is Pnma,Z=4 and the cell dimensions area=12.123,b=14.824, andc=10.378 Å, resp. The structure was solved by direct methods and refined by block-diagonal least-squares to a finalR-value of 6.4% (weighted 3.2%) for 1295 independent reflexions. The compound (C₈H₄N₂)₃BCl consists only of three isoindolyl groups in contrast to the normal phthalocyanines and is not planar but bowl-shaped. The molecule possesses 3m symmetry within the limits of accuracy. The B-atom is co-ordinated tetrahedrally by the three isoindolyl N-atoms and the Cl-atom. The B−Cl distance is 1.863 Å. The B−N distances (1.468 Å) are shortened considerably as a result of steric effects. The π-electrons of the 14-membered inner ring form a quasiaromatic conjugated π-system.