Claims:
1. An improved process for preparing 5-Aminolevulinic acid hydrochloride of Formula-la
(a) Esterifying succinic anhydride in presence of lewis acid and solvent
(b) Chlorinating 4-isopropoxy-4-oxobutanoic acid with thionyl chloride
(c) Acylating isopropyl 4-chloro-4-oxobutanoate with 2-benzamidoacetic acid in
presence of base
(d) Hydrolyzing isopropyl 4-oxo-4-(5-oxo-2-phenyl-4,5-dihydrooxazol-4-yl)butanoate in presence of hydrochloric acid
(e) Isolating 5-Aminolevulinic acid hydrochloride

2. The process according to claim 1, wherein solvent selected from the group consisting of methanol, isopropanol, Isobutanol, toluene, dichloromethane, acetone or mixtures of.
3. The process according to claim 1, wherein base selected from the group consisting of 4-picoline, pyridine, triethylamine or mixtures of.
4. The process according to claim 1, wherein aluminium chloride.