Synthesis of homometallic divalent lanthanide organoimides from benzyl complexes.

The reaction of LnI2(thf)2 with benzyl potassium affords the homoleptic benzyl complexes [Ln(CH2Ph)2]n of samarium, europium, and ytterbium. In the cases of Eu and Yb, the treatment of [Ln(CH2Ph)2]n with one equivalent of 2,6-diisopropylaniline gives access to tetrameric organoimide complexes [(thf)Ln(μ3-NDipp)]4, representing the first examples of homometallic Ln(ii) imides. This study revealed that the Yb(ii) organoimide chemistry is significantly different from that of calcium.