Structures of Iodophenyltellurium(II) and Diiododi-(beta-naphtyl)tellurium(IV)

Structures of Iodophenyltellurium(II) and Diiododi-(b-naphtyl-tellurium(IV)

Abstract. The reactions between diphenyl ditelluride, (PhTe)2, or di(b-naphtyl)-ditelluride, (b-naphtylTe)2, with equivalent amounts of iodine have been reinvestigated and the crystal and molecular structures of iodophenyltellurium(II), (PhTeI)4, and diiododi-(b-naphtyl)-tellurium(IV), (b-naphtyl)2TeI2, have been determined.
The structure of iodophenyltellurium(II) (space group Cc, a = 13.850(5) Å, b = 13.852(3) Å, c = 16.494(6) Å and b = 101.69(2)°, Z = 4) is built up by four PhTeI units which are linked by weak Te-Te interactions with Te-Te distances between 3.152(5) Å and 3.182(4) Å. The angles between the tellurium atoms are approximately 90° giving an almost perfect square. Long range secondary bonds (Te ---- I: about 4.2 Å) link the tetrameric units to give an infinite two-dimensional network.
Iodo(b-naphtyl)tellurium(II) is less stable than the phenyl derivative. Solutions of this compound decompose under formation of elemental tellurium and (b-naphtyl)2TeI2. (b-Naphtyl)2TeI2 crystallises in the monoclinic space group C 2/c (a = 21.198(6) Å, b = 5.8921(8) Å, c = 16.651(5) Å, b = 114.77(2)°). The tellurium atom is situated on a two-fold crystallographic axis and Te-I and Te-C bond lengths of 2.899(1) and 2.108(7) Å have been determined.