Question

How will you bring about the following conversion in not more than two steps?
Propanone to propene

Benzoic acid to benzaldehyde

Ethanol to 3-hydroxy butanal

Benzene to m-ntroacetophenone

Benzaldehyde to benzophenone

Bromobenzene to l-phenylethanol

Benzaldehyde to 3-phenyl propan-1-ol

Benzaldehyde to $\alpha$-hydroxy phenyl acetic acid

Benzoic acid to m-nitrobenzyl alcohol

Answer 1

Propanone to propene
$\underset{Propanone}{C{H}_{3}COC{H}_3}\underset{2\left(H\right)}{\overset{LiAI{H}_4}{\to }}\underset{\underset{Propan-2-ol}{OH}}{\underset{|}{C{H}_{3}CHC{H}_3}}$
$\underset{Heat}{\overset{H_{2}S{O}_4\left(Conc\right)}{\to }}\underset{Propene}{C{H}_{3}CH=C{H}_3}$

Benzoic acid to benzaldehyde

Ethanol to 3-hydroxy butanal

Benzene to m-ntroacetophenone

Benzaldehyde to benzophenone
$\underset{Benzaldehyde}{C_6{H}_{5}CHO}\underset{KMn{O}_4}{\overset{Oxidation}{\to }}\underset{Benzoicacid}{C_6{H}_{5}COOH}\underset{Heat}{\overset{Ca(OH{)}_2}{\to }}\underset{Benzophenone}{C_6{H}_{5}CO{C}_6{H}_5}$

Bromobenzene to l-phenylethanol

Benzaldehyde to 3-phenyl propan-1-ol

Benzaldehyde to $\alpha$-hydroxy phenyl acetic acid

Benzoic acid to m-nitrobenzyl alcohol