Patent ID: 8501962

Claim:
A process for the preparation of high purity sunitinib malate of formula-I(a), which comprises:— (i) reacting tertiary butylacetoacetate, ethyl acetoacetate, sodium nitrite and Zn dust in acetic acid medium to get a diester derivative of formula-II (ii) selective decarboxylation of compound of formula-II in alcohol-aqueous HCl medium to get half ester derivative of formula-III (iii) formylation at 2 nd position of pyrrole ring of formula-III using DMF-POCl 3 complex to get aldehyde-ester derivative of formula-IV (iv) selective hydrolysis of ester moiety of formula-IV using aqueous KOH-alcohol medium, extracting unreacted compound of formula-IV using an organic solvent and isolating the aqueous solution by adjusting the pH to get aldehyde-carboxylic acid derivative of formula-V (v) amidation of carboxylic acid derivative of formula-V using 2-diethyl aminoethyl amine of formula-VI in presence of dicyclohexyl carbodimide and 1-hydroxy benzotriazole to get aldehyde-amide derivative of formula-VII (vi) selective reduction of carbonyl functionality of 5-fluoro isatin of formula-VIII using aqueous hydrazine hydrate to get 5-fluoro-2-oxindole of formula-IX (vii) condensation of aldehyde-amide derivative of formula-VII and 5-fluoro-2-oxindole of formula-IX in alcohol medium optionally employing a catalyst to get Sunitinib base of formula-I (viii) conversion of Sunitinib base of formula-I into its pharmaceutically acceptable malate salt of formula-I(a) (1:1 mixture) using L(−)-malic acid in an organic solvent