Organometallic Compounds of the Lanthanides 182 [1]. Calcium and Neodymium Complexes Containing the dpp-BIAN Ligand System: Synthesis and Molecular Structure of [(dpp-BIAN)CaI(THF)2]2 and [(dpp-BIAN)NdCl(THF)2]2

Oxydation of (dpp-BIAN)Ca(THF)4 with 0.5 equiv. of I2 in THF yields [(dpp-BIAN)CaI(THF)2]2 (1). A corresponding neodymium compound [(dpp-BIAN)NdCl(THF)2]2 (2) has been obtained by reaction of (dpp-BIAN)Na2 with NdCl3 in THF. The X-ray single crystal structure analyses show 1 and 2 to be isostructural dimers containing octahedrally coordinated metal atoms bridged by the respective halides. The chelating dpp-BIAN ligand acts as a radical anion in the Ca2+ complex 1 and as a dianion in the Nd3+ complex 2, respectively.