Dibenzylstrontium and -barium: Simple Molecules with Complex Structures

The reactions between two equivalents of PhCH2K and AeI(2) (Ae = Ca, Sr, Ba) in THF give the alkaline earth metal benzyls [(PhCH2)(2)Ca(THF)(4)] (3), [(PhCH2)(4)Sr-2(THF)(3)] (4), and [(PhCH2)(6)Ba-3(THF)(4)] (5), as orange, crystalline solids in good yield. While 3 crystallizes as a molecular species, compound 4 crystallizes as a ribbon polymer and 5 crystallizes as a 2-dimensional sheet in which the metal ions are coordinated by either benzyl and THF molecules or benzyl ligands alone.