What is the major organic product obtained from the following sequence of reactions?

R)-2-Methylpentanenitrile
S)-2-Methylpentanenitrile
C)(±)-2-Methylpentanenitrile
D)trans-2-Butene

Question

What is the major organic product obtained from the following sequence of reactions?

R)-2-Methylpentanenitrile 
S)-2-Methylpentanenitrile 
C)(±)-2-Methylpentanenitrile 
D)trans-2-Butene

Quizplus · Accepted Answer

The starting material, 2-methylbutanal, undergoes a Grignard reaction with methylmagnesium bromide to form the alcohol, (R)-2-methylpentan-2-ol. This is then dehydrated with sulfuric acid to form (R)-2-methylpentene. Finally, the nitrile group is added by reaction with sodium cyanide in the presence of sulfuric acid, resulting in the formation of (R)-2-methylpentanenitrile as the major organic product.

What Is the Major Organic Product Obtained from the Following