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  • Halogen-bonded co-crystal containing 1,3-diiodoperchlorobenzene and the photoproduct rtct -tetrakis(pyridin-4-yl)cyclobutane resulting in a zigzag topology
Title: Halogen-bonded co-crystal containing 1,3-diiodoperchlorobenzene and the photoproduct rtct -tetrakis(pyridin-4-yl)cyclobutane resulting in a zigzag topology
The formation and crystal structure of a zigzag network held together by I...N halogen bonds is reported. In particular, the halogen-bond donor is 1,3-diiodoperchlorobenzene ( C 6 I 2 Cl 4 ) while the acceptor is the photoproduct rtct -tetrakis(pyridin-4-yl)cyclobutane ( TPCB ). Curiously, within the resulting co-crystal ( C 6 I 2 Cl 4 )·( TPCB ), the photoproduct accepts only two halogen bonds between neighbouring 4-pyridyl rings and as a result behaves as a bent two-connected node rather than the expected four-connected centre. In addition, the photoproduct, TPCB , is also found to engage in C—H...N hydrogen bonds, forming an extended zigzag chain.  more » « less
Award ID(s):
2117129
PAR ID:
10433054
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Acta Crystallographica Section E Crystallographic Communications
Volume:
79
Issue:
3
ISSN:
2056-9890
Page Range / eLocation ID:
212 to 215
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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    The formation of a photoreactive cocrystal based upon 1,2-diiodoperchlorobenzene ( 1,2-C 6 I 2 Cl 4 ) and trans -1,2-bis(pyridin-4-yl)ethylene ( BPE ) has been achieved. The resulting cocrystal, 2( 1,2-C 6 I 2 Cl 4 )·( BPE ) or C 6 Cl 4 I 2 ·0.5C 12 H 10 N 2 , comprises planar sheets of the components held together by the combination of I...N halogen bonds and halogen–halogen contacts. Notably, the 1,2-C 6 I 2 Cl 4 molecules π-stack in a homogeneous and face-to-face orientation that results in an infinite column of the halogen-bond donor. As a consequence of this stacking arrangement and I...N halogen bonds, molecules of BPE also stack in this type of pattern. In particular, neighbouring ethylene groups in BPE are found to be parallel and within the accepted distance for a photoreaction. Upon exposure to ultraviolet light, the cocrystal undergoes a solid-state [2 + 2] cycloaddition reaction that produces rctt -tetrakis(pyridin-4-yl)cyclobutane ( TPCB ) with an overall yield of 89%. A solvent-free approach utilizing dry vortex grinding of the components also resulted in a photoreactive material with a similar yield. 
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  2. ; (, Acta Crystallographica Section C Structural Chemistry)
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  3. ; (, Acta Crystallographica Section C Structural Chemistry)
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  4. ; ; (, Molecules)
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