Match List I with List II:

List-I (Compound)	List-II (pK_a$pK_a$ value)
A. Ethanol	I. 10.0
B. Phenol	II. 15.9
C. m-Nitrophenol	III. 7.1
D. p-Nitrophenol	IV. 8.3

Choose the correct answer from the options given below :

### Related Formula textPhenol + textCHCl_3 + textNaOH xrightarrowtextH^+ text2-Hydroxybenzaldehyde (Salicylaldehyde)$$\text{Phenol} + \text{CHCl}_3 + \text{NaOH} \xrightarrow{\text{H}^+} \text{2-Hydroxybenzaldehyde (Salicylaldehyde)}$$ ### Core Logic This chemical sequences details the well-known Reimer-Tiemann reaction mechanism. The treatment of phenol with alkaline chloroform generates a dichlorocarbene intermediate (:textCCl_2$:\text{CCl}_2$), which acts as an electrophile and specifically attacks the ortho position of the phenoxide ring system. Subsequent basic hydrolysis converts the functional intermediate to an aldehyde block, providing 2-hydroxybenzaldehyde as the major final product. ### Step 1: Visual Pathway Validation The step-by-step schematic transforms structural blocks through standard intermediates:

### Pattern Recognition Chloroform + Base + Phenol yields formylation at the ortho site, producing salicylaldehyde (2-hydroxybenzaldehyde). ### Evaluation Rubric / Model Answer null ### Chapter Mix Class 12 Chemistry: Organic Compounds Containing Oxygen

### Related Formula textEster xrightarrowtextDIBAL-H textAldehyde$$\text{Ester} \xrightarrow{\text{DIBAL-H}} \text{Aldehyde}$$ ### Core Logic Breaking down the multistep pathway: * **Step A**: The ester group is selectively reduced to an aldehyde using textDIBAL-H$\text{DIBAL-H}$ at low temperature without affecting other domains. * **Step B**: An intramolecular Aldol condensation occurs in the presence of base (textNaOH$\text{NaOH}$) to generate the bicyclic alpha,beta$\alpha,\beta$-unsaturated carbonyl framework. * **Step C**: Clemmensen reduction (using amalgamated zinc and hydrochloric acid, textZn(Hg)/HCl$\text{Zn(Hg)/HCl}$) reduces the ketone group to a hydrocarbon block. ### Step 1: Verification The step-by-step mechanism proceeds precisely as illustrated below:

### Pattern Recognition DIBAL-H stops cleanly at the aldehyde phase from an ester precursor, preparing the molecule perfectly for subsequent aldol ring closures. ### Evaluation Rubric / Model Answer null ### Chapter Mix Class 12 Chemistry: Organic Compounds Containing Oxygen