Question

Butene when treated with chlorine at about 500${}^o$C forms:

• A. MeCH${}_2$CHCl - CH${}_2$Cl
• B. MeCH(Cl)-CH=CH${}_2$
• C. ClCH${}_2$CH${}_2$CH = CH${}_2$
• D. MeC(Cl${}_2$)CH=CH${}_2$

Answer 1

Answer: (B)

MeCH(Cl)-CH=CH${}_2$

Butene when treated with chlorine at about 500 ${}^{0}C$ forms 3-chloro-1-butene. in this reaction, the allylic H is replaced with Cl.
$C{H}_3-C{H}_{2}CH=C{H}_2\underset{{500}^{o}C}{\overset{Cl}{\to }}C{H}_3-CHCl-CH=C{H}_2$