CBSE Class 12 · 2019 · Alcohols Phenols and EthersShort Answer

Write the structures of compounds A and B in each of the two reaction sequences shown in the figure.

Solution

Work each printed sequence left to right:
• where the figure shows an alkene with (i) B

_{2}

_{6}

, (ii) H

_{2}

_{2}

/OH

^{-}

: A is the trialkylborane and B the \textbf{anti-Markovnikov alcohol} (OH on the terminal carbon);
• where it shows phenol entering CHCl

_{3}

/NaOH or CO

_{2}

/NaOH: A is the ortho-substituted sodium salt and B, after acidification, \textbf{salicylaldehyde} (Reimer–Tiemann) or \textbf{salicylic acid} (Kolbe).
Read the exact reagents off the figure and write A and B at those stages.

CBSE Class 12 Board · 2019 · Subjective

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