HBR/{{H}_{2}}{{O}_{2}}}\] \[C{{H}_{3}}C{{H}_{2}}C{{H}_{2}}C{{H}_{2}}Br\xrightarrow{{{C}_{2}}{{H}_{5}}ONa}\] \[C{{H}_{3}}{{(C{{H}_{2}})}_{3}}O{{C}_{2}}{{H}_{5}}\] In PRESENCE of \[{{H}_{2}}{{O}_{2}},HBr\] adds in anti-Markovnikov's way (peroxide effect).