CHELATING TRIARYLGERMYL ANIONS AS LIGANDS IN LANTHANIDE CHEMISTRY - SYNTHESIS OF LN[GEAR3](2)[AR=C6H4(2-CH(2)NME(2)) LN=SM, YB] AND THE CRYSTAL-STRUCTURE OF AN UNUSUAL MU-(O-TOLYLENE)DIGERMANE BY-PRODUCT

The synthesis of substituted triarylgermyl potassium reagents KGeAr3 [ Ar = C6H4(2-CH(2)NMe(2)) and C6H3(2-OMe)(5-Me)] and their reactions wi th YbI2 and SmI2 are described. Clean formation of Ln[GeAr3](2) comple xes is observed for Ar = C6H4(2-CH(2)NMe(2)) in which the lanthanide c entre is six-coordinate with each germyl anion functioning as a triden tate ligand. Reaction of KGeAr3 [Ar = C6H3(2-OMe)(S-Me)] with LnI(2) d id not produce Ln[GeAr3](2) complexes cleanly. This failure was traced to competing metallation of the diethyl ether solvent. Crystals of a mu-o-tolylenedigermane byproduct were however isolated from the YbI2 r eaction and crystallographically characterized. The latter compound re presents the first example of the mu-o-phenylenedigermane class of com pounds to be reported.