[12]Annulene and Two Simple Derivatives – Aromaticity?

Chemistry
Complex chemicals possess names almost equally complex. Occasionally, a simpler nomenclature can be employed. For basic aromatic compounds, composed of a ring of alternating single and double bonded carbon atoms in a ring, the name [n]annulene has been is commonly used. Examples, including [12]annulene are given below. Aromaticity We won't go into the theory behind aromaticity. What we will do is lay out the basic factors that students use to determine if a compound is aromatic. 1. The ring is composed of conjugated single and double bonds (...−C=C−C=...). 2. The molecule is relatively flat. 3. The number of available π-electrons equals 4n + 2 (a Hückel number), where n is generally a small positive integer.¹ 4. Crowding does not severely limit or prevent aromaticity. 5. Ring size affects aromaticity, but…
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The Curiously Stable Dodecaborate Dianion

Chemistry
There is a lot of talk concerning the chemistry of carbon. And this is totally appropriate. The chemistry of carbon is the chemistry of life. But little is known about boron, which is right next door to carbon on the periodic table of the elements. Yet, boron is a most interesting element. For one thing, boron, like carbon, is capable of bonding to itself. Boron Bonds to Itself There are many compounds in which the element does just that, it bonds to itself. Consider a few of its combinations with hydrogen (see the image). As you advance to larger boron-hydrogen structures, however, it becomes clear the molecular bonding for boron differs considerably from the hydrocarbons. Dodecaborane Dodecaborane somewhat resembles dodecahedrane (C20H20) in outward appearance, even though in terms of bonding,…
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