Crystal structures of a series of 3,8-di[-2-aryl-1-azenyl]-1,3,6,8-tetraazabicyclo[4.4.1]undecanes

The crystal and molecular structure of a series of 3,8-di[-2-aryl-1-azenyl]-1,3,6,8-tetraazabicyclo[4.4.1]undecanes (1-5) have been determined by single crystal X-ray diffraction analysis. In all five compounds, the tetraazabicycloundecane portion of the molecule assumes a cage-like, folded structure with the aryltriazene moieties aligned approximately parallel; the structure is held in the folded configuration by either intramolecular or intermolecular pi-pi stacking forces. Crystal data: 1 C19H22N10O4, monoclinic space group P2(1)/c, a = 10.1846(7), b = 9.9556(7), c = 20.819(2) Angstrom, beta = 98.725(1)degrees, V = 2086.5 (3) Angstrom(3), Z = 4; 2 C23H28N8O4, triclinic, space group <P(1)over bar>, a = 6.7064(7), b = 12.9662(14), c = 14.054(2) Angstrom, alpha = 94.796(2), beta = 91.621(2), gamma = 104.836(2)degrees, V = 1175.7(2) Angstrom(3), Z = 2; 3 C19H22N10O4, monoclinic, space group P2(1)/c, a = 14.237(2); b = 13.520(2), c = 11.5805(12) Angstrom, beta = 113.514(2)degrees, V = 2044.0(4) Angstrom(3), Z = 4; 4 C21H22Ni10, monoclinic, space group C2/c, a = 54.247(3), b = 11.5531(7), c = 12.9670(7) Angstrom, beta = 95.710(1)degrees, V = 8086.4(8) Angstrom(3), Z = 16; 5 C25H32N8O4, monoclinic, space group P2(1)/c, a = 10.2908(7), b = 16.5687(12), c = 15.1662(10) Angstrom, beta = 94,188(1)degrees, V = 2579.0(3) Angstrom(3), Z = 4.