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Published on: November 15, 2017
1,3-diphenylisobenzofuran
René T Boeré1, Peter W Dibble, Kristapher E Fischer
1Department of Chemistry and Biochemistry, University of Lethbridge, Lethbridge, AB, Canada T1K 3M4.
Acta Crystallographica. Section E, Structure Reports Online
|January 5, 2011
Summary
The structure of 1,3-diphenyl-2-benzofuran reveals alternating short and long carbon-carbon bonds, suggesting a polyene character. This is the first reported crystal structure of the parent compound, distinct from its Diels-Alder adducts.
Area of Science:
- Organic Chemistry
- Crystallography
Background:
- 1,3-diphenyl-2-benzofuran is a commercially available furan derivative.
- Over 60 Diels-Alder adducts of this compound have been structurally characterized.
- The crystal structure of the parent compound itself has not been previously reported.
Purpose of the Study:
- To determine and report the crystal structure of 1,3-diphenyl-2-benzofuran.
- To analyze the bond lengths and electronic character of the benzofuran ring system in the parent compound.
Main Methods:
- Single-crystal X-ray diffraction analysis was employed to elucidate the molecular structure.
- Analysis of bond lengths within the benzofuran ring system was performed.
Main Results:
- The crystal structure of 1,3-diphenyl-2-benzofuran (C(20)H(14)O) was determined.
- A distinct alternation of short (mean 1.361 Å) and long (mean 1.431 Å) C-C bonds was observed around the benzofuran ring.
- These bond length variations indicate a predominantly polyene character for the benzofuran system.
Conclusions:
- The study provides the first crystallographic report on the parent 1,3-diphenyl-2-benzofuran.
- The observed bond alternation confirms a significant polyene character, influencing its chemical reactivity.
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