4,4-Dimethoxy-2-butanone → HCID 68659001, compound

Participants

Reaction Steps

To a stirred solution of 0.30 mL (2.4 mmol) of 4,4-dimethoxy-2-butanone in 2 mL of glacial acetic acid at 95° C. was added 448 mg (2.0 mmol) of tert-butyl 3-amino-2,6-dihydropyrrolo[3,4-c]pyrazole-5(4H)-carboxylate as a solution in 8 mL of glacial acetic acid over 40 min. The reaction mixture was stirred for an additional 1.5 h, cooled to ambient temperature and the solvent evaporated in vacuo to afford the title compound as a 5:3 mixture with tert-butyl 2-methyl-7H-pyrrolo[3′,4′:3,4]pyrazolo[1,5-a]pyrimidine-8(9H)-carboxylate and was used in Step B without purification. LC/MS 275.2 (M+1).

Provenance & Evidence