Abstract: A process for preparing a compound represented by Formula [1], the process comprising a step of hydrolyzing a compound represented by Formula [2] under an acidic or basic condition, and a step of reacting a compound represented by Formula [3] with a metal acetate salt, and a step of halogenating a compound represented by Formula [4]; a process for preparing a compound represented by Formula [1] comprising a step of reacting a compound represented by Formula [3] with a metal acetate salt, and then, adding alcohol, water, or base to the reaction solution to perform reaction; a process for preparing a compound represented by Formula [1] comprising a step of reacting a compound represented by Formula [3] under a presence or absence of a base, an ionic liquid and a metal sulfate salt, in water or a mixed solvent of water and an organic solvent; a compound represented by Formula [2] or a salt of the same; and a compound represented by Formula [3] or a salt of the same.