

$X\xrightarrow{{{\text{Bromination}}}}Y\xrightarrow{{NaN{O_2} + HCl}}Z\mathop {\xrightarrow{{{\text{Boiling}}}}}\limits_{{C_2}{H_5}OH} {\text{Tribromobenzene}}$

$I.$ ${Sn}-{HCl}$ $II.$ ${Sn}-{NH}_{4} {OH}$ $III.$ ${Fe}-{HCl}$ ${IV} . {Zn}-{HCl}$ $V.$ ${H}_{2}-{Pd}$ $VI.$ ${H}_{2}-$ રેની નિકલ