Processes for the preparation of ivacaftor

A process for the preparation of ivacaftor of Formula I or a pharmaceutically acceptable salt thereof,

• comprising:
• a1) reacting a compound of Formula VI with a dimethyl formamide-dimethyl amine complex to obtain a compound of Formula VII,
• wherein ‘X’ represents a halo and ‘R1’ represents either hydrogen or a protecting group;
• b1) reacting the compound of Formula VII with a source of ammonia to obtain a compound of Formula VIII,
• c1) cyclizing the compound of Formula VIII to obtain the ivacaftor of Formula I, when R1 is hydrogen, or to obtain a compound of Formula IX, when R1 represents a protecting group and deprotecting the Formula IX in a deprotecting agent to obtain the ivacaftor,