Effect of methyl-ene ethyl-ene linkers on structural properties of -butyl and mesityl bis-(imidazolium) bromide salts.

The crystal structures of ligand precursor bis-(imidazolium) salts 1,1'-methyl-enebis(3--butyl-imidazolium) dibromide monohydrate, CHN ·2Br·HO or [ NHCMe][Br]·HO, 1,1'-(ethane-1,2-di-yl)bis-(3--butyl-imidazolium) dibromide dihydrate, CHN ·2Br·2HO or [ NHCEt][Br]·2HO, 1,1'-methyl-enebis[3-(2,4,6-tri-methyl-phen-yl)imidazolium] dibromide dihydrate, CHN ·2Br·2HO or [NHCMe][Br]·2HO, and 1,1'-(ethane-1,2-di-yl)bis-[3-(2,4,6-tri-methyl-phen-yl)imidazolium] dibromide tetra-hydrate, CHN ·2Br·4HO or [NHCEt][Br]·4HO, are reported. At 293 K, [ NHCMe][Br]·HO crystallizes in the 2/ space group, while [ NHCEt][Br]·2HO crystallizes in the 2/ space group at 100 K. At 112 K, [NHCMe][Br]·2HO crystallizes in the ortho-rhom-bic space group while [NHCEt][Br]·4HO crystallizes in the 2/ space group at 100 K.