Lithia­tion of the diamino­pyridine protio‐ligand MeC(2‐C 5 H 4 N){CH 2 N(H)Mes} 2 (Mes = 2,4,6‐C 6 H 2 Me 3 )

Reaction of the diamido­pyridine protio‐ligand MeC(2‐C 5 H 4 N){CH 2 N(H)Mes} 2 (Mes = 2,4,6‐C 6 H 2 Me 3 ) with butyl­lithium in diethyl ether affords the compound (diethyl ether)(μ 4 ‐2‐{6‐[1,3‐dimethyl‐3‐(2‐pyrid­yl)‐1,4‐bis­(2,4,6‐trimethyl­anilinio)but­yl]‐2‐pyrid­yl}‐2‐methyl‐1,3‐bis­(2,4,6‐tri­methyl­anilinio)propane)tetra­lithium(I), [Li 4 (C 55 H 64 N 6 )(C 4 H 10 O)] or Li 4 [MeC(2‐C 5 H 4 N){CH 2 N(Mes)}CHN(2,4,6‐C 6 H 2 ‐Me 2 C(Me)(2,2′‐C 5 H 3 N){C(Me)}(CH 2 NMes) 2 ](OEt 2 ), which shows the methyl­ation of the pyridyl ortho ‐position with a methyl group of one of the mesityl groups. The complex contains four Li atoms, each of which is chemically distinct. The tetra­anionic ligand contains two protio‐ligand units which are fused together into a single entity. The structure contains two disordered mol­ecules of diethyl ether, one of which is coordinated to one of the Li atoms.