what would the major product be?

Question

The picture of my question is below - I couldn't upload it on Wyzant for some reason

I know the first part is a Grignard reaction but I don't know what the second step is and what it would produce

https://imgur.com/a/ZFPytWM

Answer 1

hi hilde,

the correct answer is "C". the grignard reagent reacts directly with the carbonyl group that looks like a ketone, and leaves the rest of that conjugated system alone. notice that they specified only ONE equivalent of grignard reagent. If there were more, they would start to react further.

the Nh4Cl (aq) is what hydrolyzes the magnesium salt MG-O back to the final OH alcohol.

In summary, a grignard reagent adds a carbon chain to the carbonyl carbon (oxidation state +2), and reduces it to an alcohol (oxidation state +1). And an easy way to count oxidation state for carbons is to ask how many bonds from the carbon to an oxygen, nitrogen, halide (like chlorine) or the second bond of a double bond). So a C=O is ox state +2 and an alcohol is ox state +1.