Secondary or tertiary alkyl halides must be used as a catalyst, such as KOH or NaOH sanction on bass, alcohol, NaNH2/NH3, high temperature and solvent as alcohol.
Must be secondary or tertiary alkyl halides used catalyst is a base to, such as KOH or NaOH in alcohol, NaNH2 / NH3 at high temperature. And the solvent is alcohol.