Enol structures of nona-2,8-dione

Below are shown the structures of the original diketone and its two enol structures, together with their electrostatic surfaces. One will cyclize to form an eight-membered ring, the other a six-membered ring.

Background Colour:

Enol to cyclize through an eight-membered ring

Original diketone
(nona-2,8-dione)

Enol to cyclize through a six-membered ring

(Red represents areas which are electron rich, blue represents areas that are electron poor)

Back to intramolecular aldol summary

P. Hammar, C. Ghobril, C. Antheaume, A. Wagner, R. Baati and F. Himo, J. Org. Chem., 2010, 75, 4728–4736.

W. Gati and H. Yamamoto, Acc. Chem. Res., 2016, 49, 1757–1768. 

 

 

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