Question

How will you synthesize the following? Give chemical equations only.
(i) 1-phenylethanol from a suitable alkene (ii) Cyclohexylmethanol with the help of alkyl halide by \( S_N2 \) reaction. (iii) Pentan-1-ol from a suitable alkyl halide.

Hint:

In organic synthesis, the choice of reaction mechanism (such as SN1, SN2, or hydroboration-oxidation) depends on the nature of the substrate and the reaction conditions. For SN2 reactions, a primary alkyl halide and a strong nucleophile are necessary for efficient substitution.

Answer 1

(i) 1-phenylethanol from a suitable alkene:
1-phenylethanol can be synthesized from styrene (ethenylbenzene) by hydroboration-oxidation reaction. The reaction is as follows: \[ \text{C}_6\text{H}_5\text{CH}=\text{CH}_2 \xrightarrow{\text{B}_2\text{H}_6} \text{C}_6\text{H}_5\text{CH}_2\text{CH}_2\text{OH} \] (ii) Cyclohexylmethanol with the help of alkyl halide by SN2 reaction:
Cyclohexylmethanol can be synthesized by performing an SN2 reaction between cyclohexyl chloride and sodium hydroxide. The reaction is as follows: \[ \text{C}_6\text{H}_1\text{CH}_2\text{Cl} + \text{NaOH} \rightarrow \text{C}_6\text{H}_1\text{CH}_2\text{OH} + \text{NaCl} \] (iii) Pentan-1-ol from a suitable alkyl halide:
Pentan-1-ol can be synthesized from 1-bromopentane by a nucleophilic substitution reaction with sodium hydroxide. The reaction is as follows: \[ \text{C}_5\text{H}_{11}\text{Br} + \text{NaOH} \rightarrow \text{C}_5\text{H}_{11}\text{OH} + \text{NaBr} \]