Share a compound : 657428-42-7

At the same time, in my other blogs, there are other synthetic methods of this type of compound, tert-Butyl 4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxylate, and friends who are interested can also refer to it.

Application of 657428-42-7, As we all know, there are many different methods for the synthesis of a compound, and people can choose the synthesis method that suits their own laboratory according to the actual situation. 657428-42-7 name is tert-Butyl 4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxylate, This compound is widely used in many fields, so it is necessary to find a new synthetic route. The downstream synthesis method of this compound is introduced below.

Step D: tert-Butyl 2-(methylsulfonyl)-2,6-dihydropyrrolo[3,4-c]pyrazole-5(4H)-carboxylate A solution of tert-butyl 4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxylate (30.0 kg, 143 mol) in 2-methyltetrahydrofuran (384 mg) was vacuum purged with nitrogen back-fill three times. The, triethylamine (25.0 kg, 247 mol) was added and the batch cooled to -10-5 C. Then, methanesulfonyl chloride (21.4 kg, 187 mol) was slowly added over 2 h. After stirring for 1 h at room temperature, water (150 kg) was added drop-wise at 5-15 C. This was followed by addition of 1N HCl solution until the pH was 7. The resulting layers were separated and the aqueous extracted with 2-methyltetrahydrofuran (106 kg). The combined organics were washed with saturated brine (2*150 kg), dried with Na2SO4, filtered, and concentrated to 60-90 L. The resulting crude was dissolved in 2-methyltetrahydrofuran (381 kg) and charged with a solution of potassium tert-butoxide in THF (805 g in 6.6 kg THF). After stirring 1 h at room temperature under nitrogen, more potassium tert-butoxide in THF (329 g in 3.0 kg THF) was added and stirred for 1 h. Analytical analysis indicates that tert-butyl 2-(methylsulfonyl)-2,6-dihydropyrrolo[3,4-c]pyrazole-5(4H)-carboxylate is the major regioisomer, so saturated brine (154 kg) was then added. After brief agitation, the layers are separated and the oragnics are washed with saturated brine (2*155 kg). The combined aqueous waste layers were then extracted with 2-methyltetrahydrofuran (103 kg). The combined organics were treated with activated carbon (8.75 kg), filtered, and dried with Na2SO4. This was then filtered and concentrated to 60-90 L. This slurry was then heated to dissolve solids at 40-50 C. and n-heptane was added (34 kg). After cooling to room temperature for 2-4 h, n-heptane (156 kg) was added and the slurry was then aged for 2-4 h at 0-5 C. The slurry was filtered and the cake washed with n-heptane. The solids were dried under vacuum at 45-55 C. to give tert-butyl 2-(methylsulfonyl)-2,6-dihydropyrrolo[3,4-c]pyrazole-5(4H)-carboxylate.

At the same time, in my other blogs, there are other synthetic methods of this type of compound, tert-Butyl 4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxylate, and friends who are interested can also refer to it.

Reference:
Patent; Merck Sharp & Dohme Corp; Merck Sharp & Dohme Ltd.; Arroyo, Itzia Z.; Krueger, Davida; Chen, Ping; Moment, Aaron J.; Biftu, Tesfaye; Sheen, Faye; Zhang, Yanfeng; US9181262; (2015); B2;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics