Organic Chemistry : Using Grignard Reagents
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Example Questions
Example Question #1 : Organic Reducing Agents
What is the product of the reaction between magnesium and any alkyl halide, in anhydrous ether?
An aldehyde
An organolithium
An alkane
An alcohol
A Grignard reagent
A Grignard reagent
The reaction between magnesium and an alkyl halide in anhydrous ether results in a Grignard reagent.
An organolithium would result from the same process, but the magnesium would need to be replaced by two equivalents of lithium. Alcohols are products of reactions between a Grignard reagent and a carbonyl.
Example Question #1 : Using Grignard Reagents
What type of reaction would ensue if the ketone compound shown was introduced to 
No reaction
Oxidation-reduction reaction
Grignard addition reaction
No reaction
Grignard reagents are known for their ability to readily attack carbonyls at the point of their carbons. However, Grignard reagents do not work in the presence of protic solvents. Rather than reacting with the desired molecule, the Grignard is so unstable that it will readily accept a proton from a protic solvent. The Grignard then becomes inert and no reaction ensues with the desired molecule.
Example Question #2 : Using Grignard Reagents
3-bromopropene was treated with
What is the final major product?
Hexanol
Hexene
6-bromohex-4-ene
Cyclohexene
Hexene
Any time we have a Grignard reagent and a primary haloalkane, we will see a substitution reaction, identical to an 
Example Question #4 : Using Grignard Reagents
What reactant(s) is/are needed to drive this reaction?
The carbons on the epoxide compound experience a slightly positive charge. As a result, a Gringard reagent can easily attack the less substituted side of the epoxide to break the ring and to form a six membered carbon chain. 
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