The length of the central bond in thieno[3-2,b]thiophene

✍ Scribed by D.T. Clark

• Book ID: 104224021
• Publisher: Elsevier Science
• Year: 1967
• Tongue: French
• Weight: 128 KB
• Volume: 8
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(00)90881-5

✦ Synopsis

me crystal structure of thieno[3-2,bjthiopbene I haa been investigated by Cox and his co-workers, ' who found the central carbon-carbon bond distance to be quite short (I.36 b, corresponding to a high TI bond order for this bond. Evana and de Seer2 calculated the I bond orders for this molecule, using the Longuet-HiggJ.ns3 pd2 hybrid model for the sulphur atom, and the bond-bond polarizabilities of naphthalene. Their results are shown in Table I, together with their predicted bond lengths. The striking feature is the large discrepancy (O-05 R) between the calculated and observed bond lengths for the central C-C bond. Longuet-Higgins4 has suggeeted that this central bond is compressed