Write the chemical reactions for the following conversions:
$1.$ Propan$-2-$ol to $2-$methylbutan$-2-$ol
$2.$ Benzenesulphonic acid to benzoquinone

(N/A) $1.$ Propan$-2-$ol to $2-$methylbutan$-2-$ol:
$CH_3-CH(OH)-CH_3 \xrightarrow{Cu, 573 \ K} CH_3-CO-CH_3$ (Propanone)
$CH_3-CO-CH_3 + CH_3CH_2MgBr \rightarrow CH_3-C(OMgBr)(CH_2CH_3)-CH_3$
$CH_3-C(OMgBr)(CH_2CH_3)-CH_3 \xrightarrow{H_3O^+} CH_3-C(OH)(CH_2CH_3)-CH_3$ ($2-$methylbutan$-2-$ol)
$2.$ Benzenesulphonic acid to benzoquinone:
$C_6H_5SO_3H \xrightarrow[(ii) H^+]{(i) NaOH, \Delta} C_6H_5OH$ (Phenol)
$C_6H_5OH \xrightarrow{Na_2Cr_2O_7, H_2SO_4} \text{Benzoquinone}$