Process for the preparation of regorafenib and its crystalline forms

A process for the preparation of Regorafenib (I)

• comprising the steps of:
• a) adding 4-Chloro-N-methyl-2-pyridinecarboxamide of Formula II
• and 4-Amino-3-fluorophenol of Formula III
• in an organic solvent in ratio between 3-8 v/w times with respect to compound of formula (II) at a temperature ranging between 20-35° C;
• b) reacting the mixture of step a) in presence of sodium/potassium tertiary butoxide in tetrahydrofuran to provide 4-(4-amino-3-fluorophenoxy) pyridine-2-carboxylic acid methyl amide (IV);
• c) reacting the compound of Formula IV with 4-chloro-3-trifluoromethylisocyanate of Formula V
• in presence of polar solvent in ratio between 3-8 v/w times with respect to compound of formula (IV) to provide Regorafenib (I);
• and
• d) optionally, purifying the Regorafenib using a polar solvent or a mixture of polar and hydrocarbon solvent, wherein the degree of purity is 99.5%.