Centrosymmetric and Chiral Porous Thorium organic Frameworks Exhibiting Uncommon Thorium Coordination Environments

日期:2016-4-21 13:27:33 人气:60 

Yuxiang Li,† Zhehui Weng,† Yanlong Wang,† Lanhua Chen, Daopeng Sheng, Yunhai Liu,* Juan Diwu, Zhifang Chai, Thomas E. Albrecht-Schmitt,and Shuao Wang,* Centrosymmetric and Chiral Porous Thorium organic Frameworks Exhibiting Uncommon Thorium Coordination Environments ,Dalton Trans., 2015, accept.

Abstract:

Solvothermal reaction of thorium nitrate and tris-(4-carboxylphenyl)phosphineoxide in DMF affords a centrosymmetric porous thorium organic framework compound [Th(TPO)(OH)(H2O)]·8H2O (1). In contrast, ionothermal reaction of the same reagents in the ionic liquid 1-butyl-2,3-dimethylimidazolium chloride results in the formation of a rare example of a chiral and porous thorium organic framework compound, [C9H17N2][Th(TPO)Cl2]·3H2O (2), which is derived solely from achiral starting materials. The geometries of the Th(IV) centers in compounds 1 and 2 are both atypical for low valent actinides, which can be best described as ten-coordinate spherical sphenocorona and irregular muffin, respectively. Large cavity of 17.5 Å (max. face to face) × 8 Å (min. face to face) with a BET surface area of 623 m2/g in compound 2 is observed. The poor stability indicated by thermalgravimetric analysis and water test for compound 2 may be originated from the unique anisotropic coordination geometry for thorium. Temperature-dependent luminescence studies for both compounds indicate the trends in intensity vary as Th–Th distance and the coordination environments of Th(IV) centers changes.

上一篇: Umbellate distortions of the uranyl coordination environment result in …