Borylated porphyrins: 5,10,15,20-tetrakis(5,5-dimethyl-1,3,2-dioxaborinan-2-yl)porphyrin nitrobenzene disolvate.
The title compound, C(64)H(66)B(4)N(4)O(8) x 2 C(6)H(5)NO(2), is a nitrobenzene solvate of a meso-tetraphenylporphyrin species with unconventional peripheral boronic ester substituents. The porphyrin units reside in the crystal on centers of inversion and exhibit a channel clathrate-type structure, wherein molecules of nitrobenzene are accommodated in tunnels of width 7-8 A that propagate through the crystal parallel to the b axis between layers of tightly offset-stacked porphyrins. The scientific significance of the reported results is twofold. They describe the synthetic route to newly functionalized building blocks for the formulation of porphyrin-based supramolecular assemblies, namely the corresponding tetraboronic acid derivative; the title compound represents an essential intermediate in this process. They reveal also that channel-type clathrates can be formed not only with the parent tetraphenylporphyrins but also with their laterally extended derivatives.
Muniappan
Sankar
S
School of Chemistry, Sackler Faculty of Exact Sciences, Tel-Aviv University, Ramat-Aviv, 69978 Tel-Aviv, Israel.
Lipstman
Sophia
S
Goldberg
Israel
I