Comparison of hydrogen bonds and diverse weak interactions of the nitro group in 2-methyl-4-nitroanilinium nitrate, bisulfate and two hexafluoridosilicates: elementary graph-set approach

作者：Daszkiewicz Marek; Mielcarek Agnieszka

来源：Acta Crystallographica Section B: Structural Science, Crystal Engineering and Materials , 2016, 72(6): 916-926.

DOI：10.1107/S2052520616016139

• optical activity
• elementary graph-set descriptor
• non-hydrogen bonding interaction
• nitro group

Crystal structures of (H2m4na)NO3 (1), (H2m4na)HSO4 (2), (H2m4na)(2)SiF6 (3) and (H2m4na)(2)SiF6 center dot 2H(2)O (4), where 2m4na = 2-methyl-4-nitroaniline, are presented. Two layers of interactions occur in the structures, N-H center dot center dot center dot O/F hydrogen bonds and interactions with the nitro group. Although diverse, hydrogen-bonding patterns are compared with each other by means of interrelations among elementary graph-set descriptors and descriptors of hydrogen-bonding patterns. Using mathematical relations, the gradual expansion of the ring patterns was shown in the crystal structures. Parallel and perpendicular arranged nitro groups form weak pi(N)(NO2)center dot center dot center dot pi(O)(NO2) and pi(N)(NO2)center dot center dot center dot O-NO2 interactions, respectively. The pi(NO2)center dot center dot center dot pi(ring) interaction has an impact to the stabilization of parallel oriented nitro groups. Generally, weak interactions constructed by the nitro group occur in the studied crystals as follows: pi(N)(NO2)center dot center dot center dot pi(O)(NO2), pi(ring)center dot center dot center dot pi(ring), C-H center dot center dot center dot O (1); pi(N)(NO2)center dot center dot center dot pi(O)(NO2), pi(N)(NO2)center dot center dot center dot O-NO2 (2); pi(N)(NO2)center dot center dot center dot pi(O)(NO2), pi(N)(NO2)center dot center dot center dot O-NO2 (3); C-H center dot center dot center dot O (4).

• 出版日期2016-12