Ammonium Acetate → HCID 131712271, compound

HRID 1680862Notes

Reaction equation

[CH3:1][O:2][C:3]1[CH:8]=[C:7]([CH2:9][NH:10][CH2:11][CH2:12][CH2:13][NH:14][CH2:15][CH2:16][CH2:17][CH2:18][NH:19][CH2:20][CH2:21][CH2:22][NH:23][CH2:24][C:25]2[CH:30]=[CH:29][C:28]([OH:31])=[C:27]([O:32][CH3:33])[CH:26]=2)[CH:6]=[CH:5][C:4]=1[OH:34].O=[C:36]1[CH2:44][CH2:43][CH2:42][C:41]2[NH:40][N:39]=[CH:38][C:37]1=2.C([O-])(=O)C.[NH4+:49].C([BH3-])#[N:51].[Na+]>>[CH3:33][O:32][C:27]1[CH:26]=[C:25]([CH2:24][NH:23][CH2:22][CH2:21][CH2:20][NH:19][CH2:18][CH2:17][CH2:16][CH2:15][NH:14][CH2:13][CH2:12][CH2:11][NH:10][CH2:9][C:7]2[CH:6]=[CH:5][C:4]([OH:34])=[C:3]([O:2][CH3:1])[CH:8]=2)[CH:30]=[CH:29][C:28]=1[OH:31].[NH2:51][N:40]1[C:41]2[CH2:42][CH2:43][CH2:44][CH2:36][C:37]=2[CH:38]=[N:39]1.[CH3:33][O:32][C:27]1[CH:26]=[C:25]([CH2:24][NH:23][CH2:22][CH2:21][CH2:20][NH:19][CH2:18][CH2:17][CH2:16][CH2:15][NH:14][CH2:13][CH2:12][CH2:11][NH:10][CH2:9][C:7]2[CH:6]=[CH:5][C:4]([OH:34])=[C:3]([O:2][CH3:1])[CH:8]=2)[CH:30]=[CH:29][C:28]=1[OH:31].[NH2:49][N:39]1[CH:38]=[C:37]2[C:41]([CH2:42][CH2:43][CH2:44][CH2:36]2)=[N:40]1

Participants

Reactant 3

HCID 517165Ammonium Acetate

HCID 5003444Sodium cyanoborohydride

HCID 131712273HCID 131712273, compound

Product 2

HCID 131712271HCID 131712271, compound

HCID 131712272HCID 131712272, compound

Procedure

In accordance with Reaction Scheme II, a 3-enol ether-6-hydroxymethylene-2-cyclohexenone, for example 3-ethoxy-6-hydroxymethylene-2-cyclohexenone, prepared by the method of Wenkert et al. J. Org. Chem., 27, 2278 (1962), is reacted with hydrazine hydrate in a mutual inert solvent such as ethanol to yield dl-6-ethoxy-4,5-dihydro-1H-indazole (VIII) and its 2H tautomer (VIIIa). Hydrolysis with acid, preferably a strong, highly ionized acid such as p-toluenesulfonic, trifluoroacetic, hydrochloric etc., yields dl-6-oxo-4,5,6,7-tetrahydro-1H-indazole (IX) and the 2H tautomer (IXa). Reductive amination of this oxo compound with ammonium acetate and sodium cyanoborohydride, or other suitable organometallic reducing agent of sufficient reducing powder, in the presence of a mutual inert solvent yields the corresponding dl-6-amino-4,5,6,7-tetrahydro-1H-indazole, (X) and dl-6-amino-4,5,6,7-tetrahydro-2H-indazole, compounds coming within the scope of formulas I and II above wherein R is H and R1 is NH2.

Workup

customHydrolysis with acid

Sources & evidence

ORD record: ord-0760cd8558a741c6be6f3b52bc19f2a8
Source dataset: uspto-grants-1981_06
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US04276300

Reaction notes

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