Omarigliptin (MK-3102) intermediate has the chemical name of 2-(Methylsulfonyl)-2,4,5,6-tetrahydropyrrolo[3,4-c]pyrazole, CAS number is 1280210-80-1, molecular formula: C12H15N3O5S2, molecular weight: 345.39, his synthesis process is adding 3.3Kg benzenesulfonic acid to 14 L of ethyl acetate to dissolve, and circulate the frozen brine to 5 to 15℃; 2.85 Kg of 2-(methylsulfonyl)-2,4,5,6-tetrahydropyrrolo[3 , 4-C]pyrazole besylate was added to 14 L of ethyl acetate to dissolve, and added to the solution of benzenesulfonic acid and ethyl acetate at 5 to 15 ℃, stirred for 30 minutes, and then dehydrated to 25 ± 5℃ After stirring at for 16 hours, the solid was obtained by centrifugation. The solid was added to 17 L of ethyl acetate and stirred for 1.5 hours. After centrifugation, the solid was washed with 4 L of ethyl acetate. The wet product was dried at -0.08 MPa to -0.1 MPa, and vacuum dried at 40 ℃ for 8 hours. The yellow solid compound was 3.16 Kg.…