Chapter 30: Q39E (page 1033)
The following reaction is an example of a [2,3] sigmatropic rearrangement. Would you expect the reaction to be suprafacial or antarafacial? Explain.
Short Answer
A [2,3] sigmatropic rearrangement involves three electron pairs (one π bond, one lone pair, and one σ bond), the orbital-symmetry rules predict a suprafacial reaction
Step by step solution
Orbital-symmetry rules
A [2,3] sigmatropic rearrangement involves three electron pairs (one π bond, one lone pair, and one σ bond), the orbital-symmetry rules predict a suprafacial reaction.
According to the rules
Electron pairs (double bonds) | Thermal reaction | Photochemical reaction |
Even number | Antarafacial | Suprafacial |
Odd number | Suprafacial | Antarafacial |
Mechanism
The mechanism for [2,3] sigmatropic rearrangement is shown as:
Over 30 million students worldwide already upgrade their learning with Vaia!
