[Telamond]

Today I synthesized β,β-diphenylpropiophenone through phenylmagnesium bromide making a conjugated addition to benzalacetophenone. I should add that the reactions occured in room temperature, without any heating. I attached what I think should be the correct reaction mechanism. I have some questions regarding this reaction.

1. Is the mechanism correctly drawn?
2. I thought that the grignard reagents were supposed to be hard nucleophiles, shouldn't they be more willingly to attack C=O instead of the C=C? Is it because it's steric hindered?
3. After the β,β-diphenylpropiophenone was formed I purified by recrystallization and through TLC I've lost all the by-products that was seen from the intermediate, leaving only the product. Should I expect any by-products other than the one in the mechanism? Will the reaction to the C=O happen at all?

Please forgive me if there's any mistakes in my English.
Thank you for your time.

[macman104]

1)  The mechanism, glancing at it, makes sense for a conjugate addition to me.
2)  Indeed, which would be my primary question.  Grignards typically are hard nucleophiles and tend to add 1,2 instead of 1,4.  Also, there should be any steric problem, because the grignard would attack the carbonyl from the above, and the whole molecule is planar.
3)  It's hard to say, given this question, I would have predicted the grignard attacking the carbonyl.

[Telamond]

I'll receive my answer through NMR tomorrow.

Just wanted to add that column chromatography is really aweful! You use all that organic solvents!
Isn't there a better way to separate/purify ~1 g sample?