Which of the following compounds gives a pink | vedclass

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(A) The reaction of phenols with phthalic anhydride in the presence of concentrated $H_2SO_4$ is a condensation reaction that forms phthalein dyes. Fo

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$2-$propylphenol

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(A) The reaction of phenols with phthalic anhydride in the presence of concentrated $H_2SO_4$ is a condensation reaction that forms phthalein dyes. For a phenol to form a phthalein dye (which shows a pink colour in basic medium),it must have a free para-position relative to the hydroxyl $(-OH)$ group to allow for the electrophilic aromatic substitution $(EAS)$ by the phthalic anhydride intermediate. In $2$-propylphenol,the para-position is free,allowing the reaction to proceed to form the corresponding phthalein derivative,which turns pink upon treatment with $NaOH$.

Which of the following compounds gives a pink colour on reaction with phthalic anhydride in conc. $H_2SO_4$ followed by treatment with $NaOH$?

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