[orgoclear]

(CH3)2CHCOCH(CH3)2+(CH3)2CMgBr (G.R) --> ________

The substrate is too much sterically hindered and too much deactivated for nucleophilic addition at the carbonyl carbon (4 ERG's) .. So in this condition what will happen ? Will a reaction occur?

[kimyacı]

 maybe grignard compound can remove of one H that adjacent to carbonyl group.because you know these hydrogens are acidic.

[azmanam]

I've also seen Grignards act as a reductant much like a MVP reduction.  Watch for that.

[orgopete]

I too was going to note the reduction to give the alkoxide and propene (in this case). If that reaction occurs, or if you form enolate directly, or if the addition is slow, the product is another alkoxide, then you can have products derived from the alkoxide, such as aldol products as well.

[Quaff]

(CH3)2CHCOCH(CH3)2+(CH3)2CMgBr (G.R) --> ________

The substrate is too much sterically hindered and too much deactivated for nucleophilic addition at the carbonyl carbon (4 ERG's) .. So in this condition what will happen ? Will a reaction occur?

Structure of GR is not correct.

[bolo]

There will a reducion occur (2,4-dimethyl-3-pentanol + propene).