Unequivocal existence of a centrosymmetric associated dimer of 4-(4-azuleno[1,2-b]thienyl)but-3-en-2-one formed by CH…OC hydrogen bonds in the crystals

✍ Scribed by Kimiaki Yamamura; Naoki Kusuhara; Yuuko Houda; Misako Sasabe; Hideki Takagi; Masao Hashimoto

• Publisher: Elsevier Science
• Year: 1999
• Tongue: French
• Weight: 192 KB
• Volume: 40
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(99)01318-0

✦ Synopsis

Unequivocal existence of a centrosymmetric associated dimer of the title compound 1 formed by C-H.. • O=C hydrogen bonds was found by X-ray crystallography. The occurrence of this hydrogen bond, as well as the observed reduction of the bond-length alternation in the seven-membered ring of 1, is understandable by the dipole resonance structures of the compound.