Potassium acenaphthylenide

Sodium anthracenide and potassium acenaphthylenide have been used. They are much milder reducing agents than naphthalides, for example ... 

If the latter reaction is performed with the very strong reductant potassium naphthalide instead of potassium acenaphthylenide which is milder, it leads to decomposition as a result of over-reduction [58]. 

Ln = Sm, Yb) were prepared in 80-90% yields by the in situ reactions of 2 equiv. of potassium acenaphthylenide, KCi d L. with Lnl2 or by reacting the naphthalene complexes of Sm and Yb with acenaphthylene (Scheme 150).623-625... 

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