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Title: Expanding reversible chalcogenide binding: supramolecular receptors for the hydroselenide (HSe − ) anion
Synthetic supramolecular receptors have been widely used to study reversible solution binding of anions; however, few systems target highly-reactive species. In particular, the hydrochalcogenide anions hydrosulfide (HS − ) and hydroselenide (HSe − ) have been largely overlooked despite their critical roles in biological systems. Herein we present the first example of reversible HSe − binding in two distinct synthetic supramolecular receptors, using hydrogen bonds from N–H and aromatic C–H moieties. The arylethynyl bisurea scaffold 1tBu achieved a binding affinity of 460 ± 50 M −1 for HSe − in 10% DMSO- d 6 /CD 3 CN, whereas the tripodal-based receptor 2CF3 achieved a binding affinity of 290 ± 50 M −1 in CD 3 CN. Association constants were also measured for HS − , Cl − , and Br − , and both receptors favored binding of smaller, more basic anions. These studies contribute to a better understanding of chalcogenide hydrogen bonding and provide insights into further development of probes for the reversible binding, and potential quantification, of HSe − and HS − .  more » « less
Award ID(s):
1625529
PAR ID:
10309019
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  
Date Published:
Journal Name:
Chemical Science
Volume:
10
Issue:
1
ISSN:
2041-6520
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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