Structural characterization and Hirshfeld surface analysis of 2-iodo-4-(penta-fluoro-λ6-sulfan-yl)benzo-nitrile

Acta Crystallogr E Crystallogr Commun. 2020 Jan 17;76(Pt 2):231-234. doi: 10.1107/S2056989020000365. eCollection 2020 Feb 1.

Abstract

The title compound, C7H3F5INS, a penta-fluoro-sulfanyl (SF5) containing arene, was synthesized from 4-(penta-fluoro-sulfan-yl)benzo-nitrile and lithium tetra-methyl-piperidide following a variation to the standard approach, which features simple and mild conditions that allow direct access to tri-substituted SF5 inter-mediates that have not been demonstrated using previous methods. The mol-ecule displays a planar geometry with the benzene ring in the same plane as its three substituents. It lies on a mirror plane perpendicular to [010] with the iodo, cyano, and the sulfur and axial fluorine atoms of the penta-fluoro-sulfanyl substituent in the plane of the mol-ecule. The equatorial F atoms have symmetry-related counterparts generated by the mirror plane. The penta-fluoro-sulfanyl group exhibits a staggered fashion relative to the ring and the two hydrogen atoms ortho to the substituent. S-F bond lengths of the penta-fluoro-sulfanyl group are unequal: the equatorial bond facing the iodo moiety has a longer distance [1.572 (3) Å] and wider angle compared to that facing the side of the mol-ecules with two hydrogen atoms [1.561 (4) Å]. As expected, the axial S-F bond is the longest [1.582 (5) Å]. In the crystal, in-plane C-H⋯F and N⋯I inter-actions as well as out-of-plane F⋯C inter-actions are observed. According to the Hirshfeld analysis, the principal inter-molecular contacts for the title compound are F⋯H (29.4%), F⋯I (15.8%), F⋯N (11.4%), F⋯F (6.0%), N⋯I (5.6%) and F⋯C (4.5%).

Keywords: crystal structure; functionalized aromatic rings; organometallic synthesis; penta­fluoro­thio; substituted arenes.

Grants and funding

This work was funded by National Science Foundation grant 1736093. National Science Foundation grant 1626103.