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Title: Conformational control through co-operative nonconventional C—H...N hydrogen bonds
We report the design, synthesis, and crystal structure of a conjugated aryleneethynyl molecule, 2-(2-{4,5-dimethoxy-2-[2-(2,3,4-trifluorophenyl)ethynyl]phenyl}ethynyl)-6-[2-(pyridin-2-yl)ethynyl]pyridine, C 30 H 17 F 3 N 2 O 2 , that adopts a planar rhombus conformation in the solid state. The molecule crystallizes in the space group P -1, with Z = 2, and features two intramolecular sp 2 -C—H...N hydrogen bonds that co-operatively hold the arylethynyl molecule in a rhombus conformation. The H atoms are activated towards hydrogen bonding since they are situated on a trifluorophenyl ring and the H...N distances are 2.470 (16) and 2.646 (16) Å, with C—H...N angles of 161.7 (2) and 164.7 (2)°, respectively. Molecular electrostatic potential calculations support the formation of C—H...N hydrogen bonds to the trifluorophenyl moiety. Hirshfeld surface analysis identifies a self-complementary C—H...O dimeric interaction between adjacent 1,2-dimethoxybenzene segments that is shown to be common in structures containing that moiety.  more » « less
Award ID(s):
1903581 1903593
NSF-PAR ID:
10292184
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Acta Crystallographica Section C Structural Chemistry
Volume:
77
Issue:
8
ISSN:
2053-2296
Page Range / eLocation ID:
485 to 489
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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