Date Published: July 01, 2011
Publisher: International Union of Crystallography
Author(s): Wesley A. Hoffert, Matthew P. Shores.
In the title compound, trans,trans-[μ-(m-phenylene)bis(ethyne-1,2-diyl)]bis[chlorido(1,4,8,11-tetraazacyclotetradecane)cobalt(III)]–trans,trans-[μ-(5-bromo-m-phenylene)bis(ethyne-1,2-diyl)]bis[chlorido(1,4,8,11-tetraazacyclotetradecane)cobalt(III)]–tetraphenylborate–acetone (0.88/0.12/2/4), [Co2(C12H4)Cl2(C10H24N4)2]0.88[Co2(C10H3Br)Cl2(C10H24N4)2]0.12(C24H20B)2·4C3H6O, with the exception of the acetylene and bromine groups, all atomic postitions are the same in the two compounds and are modeled at full occupancy. The CoIII ions are six-coordinate with acetylide and chloride ligands bound to the axial sites and the N atoms from the cyclam rings coordinated at the equatorial positions. N—H⋯O and N—H⋯Cl hydrogen-bonding interactions help to consolidate the crystal packing.
Metallodendrimers are of interest for their unique catalytic and optical properties, see: Mery & Astruc (2006 ▶); Onitsuka & Takahashi (2003 ▶). For Pt(II)- and Ru(II)-containing dendrimers based on a 1,3,5-triethynylbenzene (H3TEB) linkage, see: Onitsuka et al. (2004 ▶); McDonagh et al. (2003 ▶). For a discussion of the structural similarity between halogen and ethynyl substituents, see: Robinson et al. (1998 ▶). For related metal–acetylide structures, see: Weyland et al. (1998 ▶); Onitsuka et al. (2004 ▶). For the structure of [(cyclam)CoCl2]Cl, see: Ivaniková et al. (2006 ▶). For the preparation of trans-[(cyclam)CoCl2]Cl, see: Bosnich et al. (1965 ▶). General Sonogashira conditions were used to prepare a mixture of 1,3,5-triethynylbenzene and 1-bromo-3,5-diethynylbenzene (Weber et al., 1988 ▶).