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  • Effect of methylene versus ethylene linkers on structural properties of tert -butyl and mesityl bis(imidazolium) bromide salts
Title: Effect of methylene versus ethylene linkers on structural properties of tert -butyl and mesityl bis(imidazolium) bromide salts
The crystal structures of ligand precursor bis(imidazolium) salts 1,1′-methylenebis(3- tert -butylimidazolium) dibromide monohydrate, C 15 H 26 N 4 + ·2Br − ·H 2 O or [ t Bu NHC 2 Me][Br] 2 ·H 2 O, 1,1′-(ethane-1,2-diyl)bis(3- tert -butylimidazolium) dibromide dihydrate, C 16 H 28 N 4 + ·2Br − ·2H 2 O or [ t Bu NHC 2 Et][Br] 2 ·2H 2 O, 1,1′-methylenebis[3-(2,4,6-trimethylphenyl)imidazolium] dibromide dihydrate, C 25 H 30 N 4 2+ ·2Br − ·2H 2 O or [ Mes NHC 2 Me][Br] 2 ·2H 2 O, and 1,1′-(ethane-1,2-diyl)bis[3-(2,4,6-trimethylphenyl)imidazolium] dibromide tetrahydrate, C 26 H 32 N 4 2+ ·2Br − ·4H 2 O or [ Mes NHC 2 Et][Br] 2 ·4H 2 O, are reported. At 293 K, [ t Bu NHC 2 Me][Br] 2 ·H 2 O crystallizes in the P 2 1 / c space group, while [ t Bu NHC 2 Et][Br] 2 ·2H 2 O crystallizes in the P 2 1 / n space group at 100 K. At 112 K, [ Mes NHC 2 Me][Br] 2 ·2H 2 O crystallizes in the orthorhombic space group Pccn while [ Mes NHC 2 Et][Br] 2 ·4H 2 O crystallizes in the P 2 1 / c space group at 100 K. Bond distances and angles within the imidazolium rings are generally comparable among the four structures. All four bis(imidazolium) salts co-crystallize with one to four molecules of water.  more » « less
Award ID(s):
1847926
NSF-PAR ID:
10350768
Author(s) / Creator(s):
; ; ; ; ; ; ;
Date Published:
Journal Name:
Acta Crystallographica Section E Crystallographic Communications
Volume:
78
Issue:
9
ISSN:
2056-9890
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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