Crystal structure of (5,14-methyl-7,12-dimethyl-1,4,8,11-tetraazadiiminecyclotetradecylene-N,N',N',N')nickel(II) bis(diisopropyldithiophosphate) complex.

The macrocyclic tetradentate Ni(II) compound was obtained in a reaction and determined by X-ray diffraction. The crystal structure shows that the molecule is centrosymmetric, and Ni atom located in a square planar coordination environment. The two [(iPrO)2PS2]- anions are outside the macrocycle complex to balance. The Ni-N bond lengths are in the range of 1.906(2) to 1.950(2)A.     

Crystal structure of (2,2'-bipyridine-N,N)(2,2',2'-triaminotriethylamine-N,N',N',N')nickel(II) diperchlorate.

An X-ray structure determination shows that the Ni(II) ion is a distorted six-coordinated octahedron by four nitrogen atoms of the tetradentate tren ligand constituting the equatorial square base, and by two nitrogen atoms of the bidentate bpy ligand in a cis position. The two six-membered rings of bpy are coplanar and almost pararell. The tetradentate ligand consists of three five-membered chelate rings in gauche coformations. The Ni-N(tren) bond lengths of this complex are almost equivalent to the reported values.     

Synthesis and structural investigation of N,N',N' '-trialkylguanidinato-supported zirconium(IV) complexes

The addition of 2 equiv of N,N',N' '-triisopropylguanidine (guanH(2)) to Zr(CH(2)Ph)(4) produced the bis(guanidinato)bis(benzyl)zirconium complex [((i)PrNH)C(N(i)Pr)(2)](2)Zr(CH(2)Ph)(2) (1). The mono(guanidinato) complex [((i)PrN)(2)C(NH(i)Pr)]ZrCl(3) (2) was accessible by the reaction of 2 equiv of guanH(2) with ZrCl(4). Guanidinium hydrochloride, [C(NH(i)Pr)(3)]Cl, is a byproduct of this reaction. When crystallized from THF, complex 2 was isolated as the THF adduct [((i)PrNH)C(N(i)Pr)(2)]ZrCl(3)(THF) (2-THF). The mixed cyclopentadienyl guanidinato complex [eta(5)-1,3-(Me(3)Si)(2)C(5)H(3)][((i)PrNH)C(N(i)Pr)(2)]ZrCl(2) (3) was prepared by treatment of [1,3-(Me(3)Si)(2)C(5)H(3)]ZrCl(3) with the in situ generated lithium triisopropylguanidinate salt. The reaction of guanH(2) with [1,3-(Me(3)Si)(2)C(5)H(3)]ZrMe(3) affords the dimethyl derivative [eta(5)-1,3-(Me(3)Si)(2)C(5)H(3)][((i)PrNH)C(N(i)Pr)(2)]ZrMe(2) (4). Definitive evidence for the molecular structures of these products is provided through single-crystal X-ray characterization of 1, 2-THF, and 3, which are presented. The extent of pi delocalization within the guanidinato ligand is discussed in the context of the metrical parameters obtained from these structural studies.