Synthesis and structural variations of substituted phenylamide complexes of the heavy alkaline earth metals calcium, strontium and barium

摘要

Starting material KN(H) C6H3-2,6-F-2 was prepared via a transamination reaction from KNH2 and 2,6-F2C6H3NH2 in THF and crystallized from 1,4-dioxane (diox) as the three-dimensional polymer [(diox)(1.5)K{N(H)-2,6-F2C6H3}center dot diox(0.5)](infinity) (1). The metathesis reaction of (THF)(4)CaI2 with KN(Me) Ph in THF yields monomeric (THF)(4)Ca[N(Me) Ph](2) (2) with a nearly linear N-Ca-N moiety of 179.84(8)degrees. The metathesis reaction of (THF)(4)CaI2 with KN(H)Mes yields trinuclear (THF)(6)Ca-3[N(H)Mes](6) (3) with a linear Ca-3 fragment and bridging 2,4,6-trimethylphenylamido groups. The reaction of 1 with (THF)4CaI(2) gives dinuclear (THF)(5)Ca-2[N(H)-2,6-F2C6H3](4)center dot 2THF (4) with three bridging and one terminally bound 2,6-difluorophenylamide. A similar reaction of (THF)(5)SrI2 with KN(H)-2,6-F2C6H3 yields dinuclear (THF)(6)Sr-2[N(H)-2,6-F2C6H3](3)I center dot THF (5) in which the iodide anion binds terminally. This iodide ligand cannot be substituted as easily by excess KN(H)-2,6-F2C6H3. The metathesis reaction of (THF)(5)BaI2 with KN(H)-2,6-F2C6H3 leads to the formation of [(THF)(2)Ba{N(H)-2,6-F2C6H3}(2)](infinity) (6) which crystallizes as a one-dimensional polymer with bridging 2,6-difluorophenylamide anions and additional Ba-F-bonds.