Synthesis and crystal structures of isolable terminal aryl hexatriyne and octatetrayne derivatives: Ar-(C triple bond C)nH (n = 3, 4).

Unprecedented stability has been observed in terminal aryl hexatriyne and terminal aryl octatetrayne derivatives by judicious choice of a bulky, nonplanar headgroup [viz., 4-(3,6-di- tert-butyl- N-carbazolyl)phenyl] which hinders topochemical intermolecular interactions in the crystal lattice.