Ccncerning tautomeric equilibria in the azocine series

✍ Scribed by Leo A. Paquette; T. Kakihana; John F. Kelly; John R. Malpass

• Publisher: Elsevier Science
• Year: 1969
• Tongue: French
• Weight: 216 KB
• Volume: 10
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(01)87912-0

✦ Synopsis

In a recent note, Huisgen and coworkers have summarized the existing data concerning the equilibrium position of the 1,3,5_cyclooctatriene (L) -bicyclo[4.2.0]octadiene (3) valence -0 I / -CD \ 1 2 tautomerism as a function of the substituents at C-7 and C-8 (cf. &).2 The German group has concluded that the large variation in the proportions of the monocyclic and bicyclic forms (12 derivatives have been studied) does not lend itself to ready theoretical interpretation at the present time. Independently, we have been examining the question of dynamic valence bond isomerization in nitrogen analogs of 1 and 2. Because of the obvious relationship between the two series and in view of the internal consistency of our observations, we communicate our results at this time with the intent of opening the entire question to scrutiny. 2-Methoxy-1-azocine (z) and its j,&dimethyl congener 112 exhibit temperature invariant (-75 to 185') nm spectra which fail tp provide any suggestion of the presence of bicyclic 3 imino ethers & and &.