$2C_2H_5OH \overset{t^o ,xt Al_2O_3}{\rightarrow} C_4H_6 + H_2 + 2H_2O$$C_6H_6 \overset{CH_3Cl, xt AlCl_3}{\rightarrow} C_6H_5CH_3 \overset{HNO_3,xt}{\rightarrow} 2,4,6 trinitro toluen ( TNT)$
$C_6H_5CH_3 \overset{KMnO_4,xt H_2SO_4}{\rightarrow} C_6H_5COOH$