Interpretation:
Ions as well as neutral molecules undergo pericyclic reactions. Classify the pericyclic reactions of the cation involved in the transformation shown in Fig. P28.49.The methyl groups are cis or trans is to be explained.
Concept introduction:
Electrocyclic reactions are a pericyclic reaction which occur intramolecularly. These reactions will result in the formation of ring compounds under the influence of heat or light. Notably, in this process one new sigma bond is formed and one old π-bond is consumed. Intriguingly, the reverse ring opening electrocyclic reaction can also be possible to occur under the same reaction mechanism but in reverse manner. In phase orbital overlap results in symmetry allowed electrocyclic reactions. Selection rules of electrocyclic reactions are;
No. of electrons | Activation mode | Stereochemistry of rotation |
4n | Thermal Photochemical |
Con Dis |
4n + 2 | Thermal Photochemical |
Dis Con |

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Chapter 28 Solutions
ORGANIC CHEMISTRY SAPLING ACCESS + ETEX
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- Calculate the proton and carbon chemical shifts for this structurearrow_forwardA. B. b. Now consider the two bicyclic molecules A. and B. Note that A. is a dianion and B. is a neutral molecule. One of these molecules is a highly reactive compound first characterized in frozen noble gas matrices, that self-reacts rapidly at temperatures above liquid nitrogen temperature. The other compound was isolated at room temperature in the early 1960s, and is a stable ligand used in organometallic chemistry. Which molecule is the more stable molecule, and why?arrow_forwardWhere are the chiral centers in this molecule? Also is this compound meso yes or no?arrow_forward
- PLEASE HELP! URGENT!arrow_forwardWhere are the chiral centers in this molecule? Also is this compound meso yes or no?arrow_forwardA mixture of C7H12O2, C9H9OCl, biphenyl and acetone was put together in a gas chromatography tube. Please decide from the GC resutls which correspond to the peak for C7,C9 and biphenyl and explain the reasoning based on GC results. Eliminate unnecessary peaks from Gas Chromatography results.arrow_forward
- Organic Chemistry: A Guided InquiryChemistryISBN:9780618974122Author:Andrei StraumanisPublisher:Cengage LearningOrganic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning


