$C{H_3}COOH\xrightarrow{{LiAl{H_4}}}A\mathop {\xrightarrow{{{H^ + }}}}\limits_{443\,K} B\xrightarrow{{B{r_2}}}C\mathop {\xrightarrow{{alc.}}}\limits_{KOH} D$

${C_2}{H_2}\xrightarrow[{HgS{O_4}/{H_2}S{O_4},60{\,^o}C}]{{{H_2}O}}X \rightleftharpoons C{H_3}CHO$
$C{{H}_{3}}\,-\,\,\overset{\overset{C{{H}_{3}}}{\mathop{|}}\,}{\mathop{C}}\,H\,\,-\,\,C{{H}_{3}}(excess)\,\,+\,\,B{{r}_{2}}\,\xrightarrow{hv}$
$\,\,\,\,C{{H}_{3}}\,-\,\,\overset{\overset{C{{H}_{3}}}{\mathop{|}}\,}{\mathop{\underset{\underset{Br}{\mathop{|}}\,}{\mathop{C}}\,}}\,\,\,-\,\,C{{H}_{3}}\,+\,\,C{{H}_{3}}\,-\,\,CH\,\,-\,\,C{{H}_{2}}\,-\,\,Br$
