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The (4n+2) rule is a consequence of the degeneracy of the π orbitals in cyclic conjugated hydrocarbon molecules. As predicted by Hückel molecular orbital theory, the lowest π orbital in such molecules is non-degenerate and the higher orbitals form degenerate pairs. For benzene the lowest π orbital is non-degenerate and can hold 2 electrons ...
To summarize, we are assuming that: (1) the energy of an electron in an isolated C(2p z) orbital is =; (2) the energy of interaction between C(2p z) orbitals on adjacent carbons i and j (i.e., i and j are connected by a σ-bond) is =; (3) orbitals on carbons not joined in this way are assumed not to interact, so = for nonadjacent i and j; and ...
Suppose that trans-cis-trans-2,4,6-octatriene is converted to dimethylcyclohexadiene under thermal conditions. Since the substrate octatriene is a "4n + 2" molecule, the Woodward–Hoffmann rules predict that the reaction happens in a disrotatory mechanism.
Singly even number, a number of the form 4n + 2 for an integer n Hückel's rule in organic chemistry, also known as the 4 n + 2 rule Topics referred to by the same term
Notably, 244 Pu, 237 Np, and 247 Cm have half-lives over a million years and would have then been lesser bottlenecks high in the 4n, 4n+1, and 4n+3 chains respectively. [6] (There is no nuclide with a half-life over a million years above 238 U in the 4n+2 chain.) Today some of these formerly extinct isotopes are again in existence as they have ...
[1] [2] Simple aromatic rings can be heterocyclic if they contain non-carbon ring atoms, for example, oxygen, nitrogen, or sulfur. They can be monocyclic as in benzene, bicyclic as in naphthalene, or polycyclic as in anthracene. Simple monocyclic aromatic rings are usually five-membered rings like pyrrole or six-membered rings like pyridine.
Kourtney Kardashian is ready for the holidays!. On Sunday, Dec. 1, The Kardashians star, 45, shared a carousel of photos that showed her home filled with Christmas decorations and multiple green ...
Unlike aromatic compounds, which follow Hückel's rule ([4n+2] π electrons) [1] and are highly stable, antiaromatic compounds are highly unstable and highly reactive. To avoid the instability of antiaromaticity, molecules may change shape, becoming non-planar and therefore breaking some of the π interactions.