deprotonated selectively at the -position by the mixed-metal alkyl-amido base [(TMEDA) x Na(Bun)(TMP)Mg(TMP)] to generate a transient intermediate which undergoes disproportionation to the disodium dimagnesium hexafuryl tri(thf) complex [{{(thf)3 x Na2}{(TMEDA) x Mg2}(2-C4H3O)6}infinity], a new type of inverse crown structure with triply-stabilized (through Mg-C , Na-O and Na...C-C interactions) furyl guest anions, and the tris(amide) [(TMEDA)x.NaMg(TMP)3].