The reaction between 4-methyl-1-pentanol and pbr3 to yield 1-bromo-4-methylpentane is probably:

It is one of the topic in alcohol reaction and the answer is an SN2-type reaction involving the protonated alkyl dibomophosphite of the alcohol as the substrate. The reaction between 4-methyl-1-pentanol and PBr3to yield 1-bromo-4-methylpentane is probably an SN2-type reaction involving the protonated alkyl dibomophosphite of the alcohol as the substrate.

The real answer is keeping the world healthy so we won’t die