p-tert-Butylcalix[6]arene hexacarboxylic acid conformational switching and octahedral coordination with Pb(II) and Sr(II).
نویسندگان
چکیده
p-tert-Butylcalix[6]arene hexaacetic acid is in a symmetric cone conformation in CHCl3, but it becomes conformationally flexible in CHCl3/CH3CN (1 : 1). In this mixture the host has a strong binding affinity towards Pb(II) and instantly forms a complex of low symmetry--shortly thereafter structural reorganization occurs resulting in a high symmetry complex of Pb(II) in an octahedral cage of carboxylates. Sr(II) and Ba(II) display similar behavior over a longer period of time.
منابع مشابه
p-tert-Butylcalix[6]arene hexacarboxylic acid as host for Pb(II), Sr(II) and Ba(II).
p-tert-Butylcalixarene hexacarboxylic acid initially binds with low symmetry, to later adopt a highly symmetric up-down alternating conformation in the presence of Pb, Sr or Ba. The conformational dynamics for the three ions are distinct, from 15 hours, to 20 days, to 38 days, respectively.
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ورودعنوان ژورنال:
- Chemical communications
دوره 50 15 شماره
صفحات -
تاریخ انتشار 2014