Acetic Acid → HCID 136017418, compound

Participants

Reaction Steps

Treatment of 2-(5-amino-3-bromo-4-nitro-1H-pyrazol-1-yl)ethanol 1 with paraformaldehyde and sodium triacetoxyborohydride in dichloroethane containing acetic acid affords 8-bromo-9-nitro-1,2,4,5-tetrahydropyrazolo[5,1-d][1,3,5]oxadiazepine 2. The reaction of the compound 2 with KOH in the presence of Pd2dba3 and 2-di-tert-butylphosphino-2′,4′,6′-triisopropylbiphenyl in 1,4-dioxane, water provides 9-nitro-1,2,4,5-tetrahydropyrazolo[5,1-d][1,3,5]oxadiazepin-8-ol 3, which upon treatment with MeI and cetylammonium bromide in 1,4-dioxane/water/KOH affords compound 8-methoxy-9-nitro-1,2,4,5-tetrahydropyrazolo[5,1-d][1,3,5]oxadiazepine 4 (J. Am. Chem. Soc. 2006, 128, 10694). Hydrogenation of 4 with Pd/C at 60 psi of hydrogen yields 8-methoxy-1,2,4,5-tetrahydropyrazolo[5,1-d][1,3,5]oxadiazepin-9-amine 5.

Provenance & Evidence