Lapatinib → p-Toluenesulfonic acid

Participants

Reaction Steps

Lapatinib prepared using the method of this embodiment can be isolated, or more preferably it can be directly converted into highly pure lapatinib ditosylate salt without isolation of the lapatinib from the step iii) reaction product mixture. The isolated lapatinib ditosylate has a HPLC purity of 97.0-99.9%, preferably >99.0%, most preferably >99.8%. The reaction product mixture from the step iii) is quenched with a basic aqueous solution such as aq. NaOH, separated and the organic phase is washed with an acidic aqueous solution such as aq. NH4Cl. The organic phase is then filtered and lapatinib ditosylate as crystalline Form I is obtained by crystallisation from the organic phase in the presence of p-toluenesulfonic acid. The lapatinib ditosylate is isolated by filtration or centrifugation, or other methods of solid isolation.

Provenance & Evidence