Question

Which is the major product obtained by hydrolysis of compounds formed by reaction between formaldehyde and ethyl magnesium bromide?
A. Ethanol
B. Propan-2-ol
C. Propan-1-ol
D. 2-Methyl-propan-2-ol

Answer 1

Hint: To answer the hydrolysis product, first of all we should find the product from the reaction between formaldehyde and ethyl magnesium bromide and then we will do the hydrolysis of that product.

Complete step by step solution:

So, the above reaction explains the question. We have to find final product B after hydrolysis from A. So, first of all we'll know about Grignard reagent. In this reaction the Grignard reagent that is present is ethyl magnesium bromide. Ethyl magnesium bromide will dissociate into ethyl with negative charge and magnesium bromide with positive charge. In the formaldehyde molecule, oxygen atoms will have negative charge, so magnesium bromide will attack on oxygen part and negative part will get attached to the carbon atom in formaldehyde.

So, from the reaction we can say that A was the intermediate product and was unstable. In the second step, hydrolysis of Product-A gives us propane-1-ol.

So, the correct answer is option C.

Note:We will now know the reason for using magnesium in Grignard reagent. The reaction to the formation of Grignard reagents requires the use of magnesium ribbon. All magnesium is covered with a passivation film of magnesium oxide, which prevents reactions to organic halide. The application of Grignard preformed reagent is also used as an initiator.
We should note that formaldehyde is a colourless, strong-smelling gas used in making building materials and many household products. It is best known for its preservative and anti-bacterial properties.