Department of Inorganic Chemistry, Indian Association for the Cultivation of Science, 2A & 2B Raja S. C. Mullick Road, Kolkata 700 032, India.
Beilstein J Org Chem. 2009 Aug 31;5:41. doi: 10.3762/bjoc.5.41.
Structural aspects of the binding of inorganic anions such as perchlorate, hydrogen sulfate, and hexafluorosilicate with the proton cage of octaaminocryptand L(1), N(CH(2)CH(2)NHCH(2)-p-xylyl-CH(2)NHCH(2)CH(2))(3)N), are examined thoroughly. Crystallographic results for a hexaprotonated perchlorate complex of L(1), [(H(6)L(1))(6+)(ClO(4) (-))]5(ClO(4) (-)).11H(2)O.CH(3)CN (1), an octaprotonated hydrogen sulfate complex of L(1), [(H(8)L(1))(8+)(HSO(4) (-))]7(HSO(4) (-)).3H(2)O.CH(3)OH (2) and an octaprotonated fluorosilicate complex of L(1), [(H(8)L(1))(8+)(HSiF(6) (-))]3(SiF(6) (2-)).(HSiF(6) (-)).15H(2)O (3), show encapsulation of one perchlorate, hydrogen sulfate and hexafluorosilicate, respectively inside the cage of L(1) in their protonated states. Further, detailed structural analysis on complex 1 reveals that the hexaprotonated L(1) encapsulates a perchlorate via two N-H...O and five O-H...O hydrogen bonds from protonated secondary nitrogen atoms of L(1) and lattice water molecules, respectively. Encapsulated hydrogen sulfate in complex 2 is "glued" inside the octaprotonated cage of L(1)via four N-H...O and six C-H...O hydrogen bonds whereas encapsulated HSiF(6) (-) in complex 3 has short contacts via six N-H...F and three C-H...F hydrogen bonds with H(8)L(1). In the cases of complexes 2 and 3, the cryptand L(1) in octaprotonated state shows monotopic encapsulation of the guest and the final conformation of these receptors is spherical in nature compared to the elongated shape of hexaprotonated state of L(1) in complex 1.
深入研究了无机阴离子（如高氯酸根、硫酸氢根和六氟硅酸根）与笼状八氨基cryptand L(1)（N(CH(2)CH(2)NHCH(2)-p-xylyl-CH(2)NHCH(2)CH(2))(3)N）质子笼的结合的结构方面。晶体学结果表明，L(1)的六质子高氯酸根配合物[(H(6)L(1))(6+)(ClO(4) (-))]5(ClO(4) (-)).11H(2)O.CH(3)CN（1）、L(1)的八质子硫酸氢根配合物[(H(8)L(1))(8+)(HSO(4) (-))]7(HSO(4) (-)).3H(2)O.CH(3)OH（2）和 L(1)的八质子氟硅酸根配合物[(H(8)L(1))(8+)(HSiF(6) (-))]3(SiF(6) (2-)).(HSiF(6) (-)).15H(2)O（3）分别在其质子化状态下将一个高氯酸根、硫酸氢根和六氟硅酸根包封在 L(1)的笼内。此外，对配合物 1 的详细结构分析表明，六质子化的 L(1)通过来自 L(1)的质子化二级氮原子和晶格水分子的两个 N-H...O 和五个 O-H...O 氢键分别包封高氯酸根。在配合物 2 中，“粘合”在 L(1)的八质子笼内的硫酸氢根通过四个 N-H...O 和六个 C-H...O 氢键与H(8)L(1)结合，而在配合物 3 中，被包封的 HSiF(6) (-)通过六个 N-H...F 和三个 C-H...F 氢键与H(8)L(1)短接触。在配合物 2 和 3 的情况下，八质子化的 cryptand L(1)显示出客体的单拓扑包封，并且这些受体的最终构象在性质上是球形的，而不是配合物 1 中六质子化状态的 L(1)的拉长形状。
