- PAR ID:
- 10301421
- Date Published:
- Journal Name:
- Chemical Communications
- Volume:
- 57
- Issue:
- 55
- ISSN:
- 1359-7345
- Page Range / eLocation ID:
- 6725 to 6727
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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We describe hydrogen bonds ( i.e. , N + –H⋯N) in combination with cation⋯π interactions to enable a cascade-like [2 + 2] photodimerization of 4-stilbazole in a salt cocrystal. A four-component crystal assembly is composed of photoactive pyridinium ion pair 4-stilbzH + ( 4-stilbz = trans -1-(4-pyridyl)-2-(phenyl)ethylene) and photostable molecule pair 4-stilbz . UV irradiation gives rctt -1,2-bis(4-pyridyl)-3,4-bis(phenyl)cyclobutane ( 4-pyr-ph-cb ) in quantitative yield. An intermediate structure 2 ( 4-stilbz )·( 4-pyr-ph-cb )2H + is isolated that undergoes a partial single-crystal-to-single-crystal transformation. The single-crystal X-ray data provides a snapshot of movements in the salt cocrystal in the course of the photodimerization.more » « less
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