azulene वाक्य
"azulene" हिंदी में azulene in a sentenceउदाहरण वाक्य
- In naphth [ " a " ] azulene, a naphthalene ring is condensed at the 1, 2-positions of azulene.
- In naphth [ " a " ] azulene, a naphthalene ring is condensed at the 1, 2-positions of azulene.
- Subsequent work showed that the isomerization of azulene to naphthalene is not readily reversible ( the kcal / mol ) . and is as follows:
- The oldest characterized thermal rearrangement of an aromatic compound was that of the isomerization of azulene to naphthalene by Heilbronner et al . in 1947.
- Another notable feature of azulene is that it violates Kasha's rule by exhibiting fluorescence from an upper-excited state ( S 2 ?
- The isomerization of unsubstituted azulene to naphthalene was the first reported thermal transformation of an aromatic hydrocarbon, and has consequently been the most widely studied rearrangement.
- For example, the cyclopentadienyl anion and the cycloheptatrienylium cation are both considered to be aromatic ions, and the azulene molecule can be approximated as a combination of both.
- Azulene has a long history, dating back to the 15th century as the azure-blue chromophore obtained by steam distillation of wormwood and named in 1863 by Septimus Piesse.
- Likewise, since the characterization of the automerization of naphthalene by Scott in 1977, azulene, benz [ " a " ] anthracene and even benzene have been described.
- The diradical mechanism has been supported by Homolysis of the weakest bond in azulene occurs, followed by a hydrogen shift and ring closure so as to retain the aromaticity of the molecule.