THE TWISTED SKELETON OF 1,9-DIAMINONONANE IN CATENA-[CATENA-MU-(1,9-DIAMINONONANE)CADMIUM(II) TETRA-MU-CYANONICKELATE(II)]-O-XYLENE(2/1)A

The Hofmann-danon-type o-xylene clathrate Cd[NH2(CH2)9NH2]Ni(CN)4.0.5(CH3)2C6H4, crystallizes in the triclinic space group P1BAR with a = 15.118(3), b = 14.048(4), c = 7.325(1) angstrom, alpha = 91.50(2), beta = 131.66(3), and gamma = 107.50(2)-degrees, V = 1051(1) angstrom 3 and Z = 2. The structure, refined to R = 0.047 using 2851 reflections, reveals a three-dimensional host framework built of the layers of a two-dimensional catena-[cadmium tetra-mu-cyanonickelate(II)] network and of the ambidentate 1,9-diaminononane (danon) bridging the Cd atoms in adjacent networks. The guest o-xylene molecule is accommodated in the cavity formed in the interlayer space similar to that in the Hofmann-daotn-type. The skeleton of the danon in the Cd-NC9N-Cd linkage takes a (gauche)2(trans)8 conformation twisted at the (gauche)2 part in contrast with the all-trans conformation of 1,8-diaminooctane in the Hofmann-daotn-type clathrate. The twisted (gauche)2 part of the danon skeleton occupies the interlayer space to such an extent that void space available for the guest o-xylene molecule decreases to half that in the Hofmann-daotn-type clathrate Cd[NH2(CH2)8NH2]Ni(CN)4.G.