Molecular compounds of "new" divalent lanthanides

The data on synthesis, structure and reactivity of lanthanide compounds (except samarium, europium and ytterbium derivatives as well as insertion phases of LnX(2) type) containing a metal in subvalent state with a particular emphasis on divalent derivatives are collected and systematized. Most of the references considered concern diiodides of Nd(II), Dy(II) and Tm(II) and their reactions with various substrates although a number of Sc(II), La(II) and Ce(II) complexes and multiple attempts to synthesize other divalent compounds of rare earth metals are also described. (C) 2004 Elsevier B.V. All rights reserved.