Identify the product A and product B in the following set of reactions.
- A-CH$_3$CH$_2$CH$_2$OH ; B-CH$_3$CH$_2$CH$_2$CH$_2$OH
- A-CH$_3$CH$_2$CH$_3$, B-CH$_3$CH$_2$CH$_3$
The Correct Option is C
Approach Solution - 1
Let's analyze the given reaction to identify the products A and B.
The reaction involves two steps starting from a given alkene:
- Product A: The first reaction involves the addition of water in the presence of an acid, \(H^+\). This is an example of acid-catalyzed hydration of alkenes. According to Markovnikov's rule, the hydroxyl group (\(OH\)) adds to the more substituted carbon. Thus, starting with propylene \(CH_3-CH=CH_2\), the major product is \(CH_3-CH(OH)-CH_3\), which is 2-propanol.
- Product B: The second reaction is hydroboration-oxidation which involves \((BH_3)_2\), followed by hydrogen peroxide \(H_2O_2\) in the presence of a base \(OH^−\). This reaction adds hydroxyl group (\(OH\)) to the less substituted carbon (anti-Markovnikov addition). For the same starting alkene \(CH_3-CH=CH_2\), the product is \(CH_3-CH_2-CH_2OH\), which is 1-propanol.
Hence, the products are:
- Product A: 2-Propanol (\(CH_3-CH(OH)-CH_3\))
- Product B: 1-Propanol (\(CH_3-CH_2-CH_2OH\))
Therefore, the correct answer matches the chemical structures shown in the option:
Approach Solution -2
(1) Hydration Reaction:
\(CH_3 - CH = CH_2 + H^+ \rightarrow CH_3 - \overset{+}{C}H - CH_3 \; \text{(More stable)}\)
(2) Hydroboration Oxidation Reaction:
\(3CH_3 - CH = CH_2 + B_2H_6 \xrightarrow{\text{THF}} 2(CH_3CH_2CH_2)_3B\)
\((CH_3CH_2CH_2)_3B + 3H_2O_2 \xrightarrow{\text{OH}^-} 3CH_3CH_2CH_2OH + H_3BO_3\) (B)
Thus the correct answer is Option 3.
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