Homochiral Frameworks Formed by Reactions of Lanthanide Ions with a Chiral Antimony Tartrate Secondary Building Unit

作者：Gao Qiang; Wang Xiqu; Jacobson Allan J^*

来源：Inorganic Chemistry, 2011, 50(18): 9073-9082.

DOI：10.1021/ic201274c

A chiral cluster compound, dipotassium bis(mu-tartrato)diantimony(III), K2Sb2L2 (H4L = L-tartaric acid), was used as a secondary building unit to react with lanthanide ions. Three series of homochiral coordination compounds were obtained: 0D [La(H2L)(H2O)(4)](2)[Sb2L2]center dot 7H(2)O (0D-La), 1D Ln(Sb2L2)(H2O)(5)(NO3)center dot H2O (1D-Ln) (Ln = La-Lu or Y, expect Pm), 2D(I) [(Ln(H2O)(5))(2)(Sb2L2)(3)]center dot 5H(2)O (2D(I)-Ln) (Ln = La, Ce, Pr), and 2D(II) [(La(H2O)(5))(2)(Sb2L2)(3)]center dot 6H(2)O (2D(II)-La). Single-crystal X-ray diffraction studies indicated that OD-La crystallizes in space group PI, and the structure contains isolated Sb2L22- units located between chains of composition La(H2L)(H2O)(4). The series of 1D-Ln compounds is isostructural and crystallizes in space group P2(1)2(1)2(1). In the structure, Sb2L22- units are coordinated to two Ln ions by two out of the four free tartrate oxygen atoms to form a linear chain. To the best of our knowledge, this is the first example of a homochiral structure that can be formed for the whole lanthanide series. In the 2D(I)-Ln structure series, which crystallizes in space group P2(1), the Sb2L22- units have two distinct coordination modes: one is the same as that found in the 1D structure, while in the other all four free tartrate oxygen atoms are coordinated to four Ln ions in a very distorted tetrahedral arrangement. The connectivity between Sb2L22- secondary units and LnO(9) polyhedra gives rise to infinite layers. 2D(II) [(La(H2O)(5))(2)(Sb2L2)(3)]center dot 6H(2)O, which crystallizes in space group C2, has a similar network to the 2D(I)-Ln compounds. The trends in lattice parameters, bond lengths, and ionic radii in the 1D-Ln series were analyzed to show the effect of the lanthanide contraction.

• 出版日期2011-9-19