C6H5NO2Sn,HCl−−−−→XNaNO2,HCl−−−−−−−−→YH3PO2−−−−→Z
The final product of the above sequence is
aniline
phenol
ethylbenzene
benzene
X is C6H5NH2;Y is C6H5N=NCl;Z is C6H6 Benzendiazonium chloride is directly reduced to benzene in the presence of hypophorous acid.