Question

Reagents used in Etard reaction (I) and Stephen reaction (II) are:

	I	II
(a)	PCC	$SnCl _{2} / HCl$
(b)	$SnCl _{2} / HCl$	$CrO _{2} Cl _{2}$
(c)	$CrO _{2} Cl _{2}$	$SnCl _{2} / HCl$
(d)	$CrO _{2} Cl _{2}$	$PCC$

• A. a
• B. b
• C. c
• D. d

Answer 1

Answer: (C)

The reagents used in Etard reaction (I) is $CrO _{2} Cl _{2}$ and Stephen reaction (II) is $SnCl _{2} / HCl$. In Etard reaction, toluene in presence of chromyl chloride gives a brown complex which gives benzaldehyde

In Stephen's reaction, nitriles underges reduction followed by hydrolysis to give aldehyde.
$C H_{3}-C \equiv N+2[H] \xrightarrow[\text{Ether}]{S n C l_{2} / H C l}$
$CH _{3}- CH = NH \cdot HCl \xrightarrow{ H _{2} O / H ^{+}}CH _{3} CHO + NH _{4} Cl$