[Covfe₂]

Hey everyone.
I've just started an organic chemistry course and I'm struggling understanding the Woodward-Fieser Rules. Mainly I think it's with identifying the functional groups. I was hoping if someone could please confirm if my wavelength max was correct for my homework and any tips in general that would help.


Base value (Cyclopentenone)            =202
Double bond extending conjugation    = 30
Exocyclic double bond                      = 5
Alkyl substituents                           = (5 x 6) = 30


wavelength max                             = 267 nm




Base value (homoannular diene)        = 253
Double bond extending conjugation    = 30
Exocyclic double bond                     = (3 x 5) = 15
Alkyl substituents                           = (5 x 5) = 25


wavelength max                            = 323 nm


thank you!

[pgk]

Yes, it is correct according Wikipedia.
But cross-check it, from spectroscopy textbooks because some authors give different values for alkyl substituents, whether being in α, β, γ or higher position from the carbonyl group.

[sjb]

For the first isn't this a cyclohexenone? Can't remember how much difference this makes and my notes are a good distance away