$RCN{\mkern 1mu} \xrightarrow{{reduction}}{\mkern 1mu} (a),$
$RCN{\mkern 1mu} {\mkern 1mu} \mathop {\xrightarrow{{(i){\kern 1pt} C{H_3}MgBr}}}\limits_{(ii){\kern 1pt} {H_2}O} {\mkern 1mu} (b),$
$RNC{\mkern 1mu} {\mkern 1mu} \xrightarrow{{hydrolysis}}{\mkern 1mu} {\mkern 1mu} (c),{\mkern 1mu} $
$RN{H_2}{\mkern 1mu} \xrightarrow{{HN{O_2}}}{\mkern 1mu} {\mkern 1mu} (d)$
${C_2}{H_5}N{H_2}\,\xrightarrow{{HN{O_2}}}a$
${C_2}{H_5}N{H_2}\,\xrightarrow{{{C_6}{H_5}CHO}}b$
${C_2}{H_5}N{H_2}\,\xrightarrow{{NOCl}}c$
${C_2}{H_5}N{H_2}\,\xrightarrow{{{C_6}{H_5}S{O_2}Cl}}d$