Question

Diborane reacts with an alkene A to give trialkyl borane as an additional product. The formed product is oxidized to alcohol by H₂O₂ in presence of aq. NaOH. Which of the following cannot be the final product?
(A) Propan-1-ol
(B) Ethanol
(C) Methanol
(D) None of these

Answer 1

Hint :The hydroboration–oxidation reaction is a two-step hydration reaction in organic chemistry that transforms an alkene to an alcohol. Where the double bond used to be, the process results in the addition of a hydrogen and a hydroxyl group. The hydroxyl group attaches to the less-substituted carbon in hydroboration–oxidation, which is an anti-Markovnikov reaction.

Complete Step By Step Answer:
The hydroboration–oxidation reaction is a two-step hydration reaction in organic chemistry that transforms an alkene to an alcohol. Where the double bond used to be, the process results in the addition of a hydrogen and a hydroxyl group. The hydroxyl group attaches to the less-substituted carbon in hydroboration–oxidation, which is an anti-Markovnikov reaction. Other hydration reactions, such as acid-catalyzed addition and the oxymercuration–reduction process, now have a more stereospecific and complementary regiochemical alternative in the form of this reaction.
 $ C{H_2} = C{H_2}\xrightarrow[{{H_2}{O_2},NaOH,{H_2}O}]{{2B{H_3}}}{C_2}{H_5}OH $
An alcohol reaction is the end result of hydroboration-oxidation. On hydroboration, the simplest alkene ethane produces alcohol, which is ethanol. As a result, the Hydroboration reaction cannot produce methanol.
Hence, Option C is the correct answer.

Note :
The chemical compound B₂H₆, also known as diborane, has the formula B₂H₆ and is made up of boron and hydrogen. It's a colourless, pyrophoric gas with an odiferous sweet odour. Boron hydride, diboron hexahydride, and bromoethane are all synonyms. Diborane is a common boron compound with a wide range of uses.