Question of the day

Which of the following reactant gives the best method of preparation of alkyl halides when reacts with alcohol?

The best method of preparation of alkyl halides is a reaction of alcohol with SOCl₂/ Pyridine because by-products formed in the reaction are SO₂ and HCl which are in gaseous form and escape into the atmosphere leaving behind pure alkyl chlorides. CH₃CH₂−OH + SOCl₂ → CH₃CH₂−Cl + SO₂↑ + HCl↑

Zn/HCl PCl₅ SOCl₂/Pyridine PCl₃ Fe/NaCl