Aromaticity

Dear Granny,

            In Organic Chemistry II, we’ve been discussing aromaticity. Aromatic compounds are a ring of carbon atoms with alternating single and double bonds. They are defined as compounds that are cyclic, planar, completely conjugated, and obey Huckel’s Rule. They received the name “aromatic” because of their distinct characteristic odors. Cyclic compounds are compounds in a ring; for example: Benzene. Planar means that the compound is flat like a sheet of paper. Conjugation is the overlap of p-orbitals in the molecule. An orbital is the cloud around the molecule that stores the electrons. P-orbitals are a dumbbell shape around the element that is attached to a double bond. Huckel’s Rule is (4n + 2), which determines the number of π electrons in the compound. Each pi electron gives 2 electrons. The easiest way I remember whether it obeys Huckel’s role, without calculating, is by remembering that the number of π electrons begins with 2 and increases by 4. So if it contains 2, 6, 10, 14, 18, 22, 26, etc.  π electrons, it is aromatic. Compounds that are cyclic, planar, and conjugated, but do not obey Huckel’s Rule, their π electrons = 4n, are considered antiaromatic. If the compound disobeys at least two of the rules to be aromatic, it is considered nonaromatic. I hope you learned something new.

Love,

 Jesslyn

Test 1

While taking the exam on Friday, I was shocked to see that we had to draw out spectrums. It was something that we hadn't practiced and during one of the first lab meetings, it was said that we wouldn't have to know how to draw them, but we would need to know how to read them. When studying, I expected that I needed to know and understand the nitrogen rule, reading and interpreting mass spectrometry, infrared spectroscopy,  ¹H NMR, and ¹³C NMR graphs. I studied primarily Ch. 14 more than Ch. 13 and I should have went over Ch. 13 more before the test. For next test, I plan to study differently. I thought there would be more Sapling problems such as #4 where the m/z was determined for two isomers and#6 labeling unknowns based on their IR absorptions.