The alkene shown reacts with $HBr$ in the presence of a peroxide, $ROOR$ . Which structure is the major product?

AStructure A
BStructure B
CStructure C
DStructure D

Answer: A

The alkene is pent-1-ene. With peroxide the bromine atom adds first to the terminal carbon (anti-Markovnikov) so that the more stable secondary radical forms, which then abstracts H from

HBr

. The product is 1-bromopentane.

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The alkene shown reacts with HBr in the presence of a peroxide, ROOR. Which structure is the major product?

Answer: A

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The alkene shown reacts with $HBr$ in the presence of a peroxide, $ROOR$ . Which structure is the major product?