4,5-Diiodo-2-phenyl-1H-imidazole

Abstract

The structure of the title compound, C9H6I2N2, contains two symmetry-independent mol­ecules. The inter­planar angles between the imidazole and phenyl ring planes are 16.35 (3) and 17.48 (6)°. Mol­ecules are connected via N—H⋯N hydrogen bonds to form zigzag chains along the b axis. The title compound is the first example of a structurally characterized 4,5-diiodo­imidazole with an organic substituent in the 2-position and without protection on the N—H group of imidazole.

C—I...N and C—I...π halogen bonding in the structures of 1-benzyliodoimidazole derivatives

“…Furthermore, 14 of these 18 structures do not exhibit any close contacts to the I atoms. The structures of five neutral N-unsubstituted iodoimidazoles are dominated by N-HÁ Á ÁN hydrogen bonds [refcodes BOWREM, BOWRUC and BOWSAJ (Andrzejewski et al, 2015), GARJUG (Chlupatý et al, 2012), and WISBUL (Ding et al, 2012)] and one structure features N-HÁ Á ÁO hydrogen bonds (KOZLIW;Jansa et al, 2015), while seven more sterically hindered imidazole derivatives do not display any major intermolecular interactions and the threedimensional structures presumably have controlled close packing based on size, shape, and polarity [GOGYOR (Delest et al, 2008), IGUANM (Al-Mukhtar & Wilson, 1978), KIRYEQ (Poverlein et al, 2007), UJOCIF (Tschamber et al, 2003), NUCRAE (Phillips et al, 1997), UNIFUS (Terinek & Vasella, 2003), and UXOXOV (Li et al, 2011)]. In contrast, three unhindered N-substituted iodoimidazoles do display C-IÁ Á ÁN halogen bonding as the major intermolecular interaction [BEQWEB (Mukai & Nishikawa, 2013), GOGYIL ISSN 2053ISSN -2296 # 2017 International Union of Crystallography (Delest et al, 2008) and HUDSUW (Byrne, 2015)].…”