Synthesis of bis(2-methoxyethylcyclopentadienyl) complexes of early lanthanide chlorides and the X-ray structure of the lanthanum complex

[(MeOCH2CH2C5H4)2Ln(µ-Cl)]2(Ln = La, Pr, and Nd) complexes have been synthesized by the reaction between LnCl3 and McOCH2CH2C5H4Na in tetrahydrofuran; a single-crystal X-ray study has shown that the lanthanum complex is a chlorine-bridged dimer with lanthanum(III) in a pseudo-octahedral co-ordination geometry if the cyclopentadienyl ring is regarded as occupying a single polyhedral vertex.