I am trying to make a fulvene molecule with dimethylamino and phenyl substituents. My worry is that the amide group donates electron density into the carbonyl carbon making it less electrophilic. enter image description here

  • $\begingroup$ Probably this won't work. I'd try an enamine route instead $\endgroup$ – Lighthart Apr 6 '16 at 2:29

Although I have no prove for this, I am almost completely certain, that this will not work.

If you look closely at the cyclopentadienyl anion, what you would like to utilise as the nucleophile, you will notice that it is and aromatic system. (It even completely obeys the Hückel rules.) There are no electrons in an orbital of suitable symmetry, that would allow attacking the π* C-O bond.
In the other molecule, as you have noted, the electrons of the nitrogen will be interacting with the π carbonyl bond. Moreover, this part of the π system is also overlapping with the aromatic system of the phenyl moiety. That will certainly remove quite a bit of charge density from the carbonyl carbon. A nucleophilic attack at that position seems highly unlikely.

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