Hydrochloric Acid → 1-(Tetrazolo[1,5-b]pyridazin-6-yl)methanamine

HRID 1987078Notes

Reaction equation

HRID 1987078 reaction equation
[N:1]1[N:2]=[N:3][N:4]2[C:9]=1[CH:8]=[CH:7][C:6]([C:10]#[N:11])=[N:5]2.Cl>[Pd].CO>[N:1]1[N:2]=[N:3][N:4]2[C:9]=1[CH:8]=[CH:7][C:6]([CH2:10][NH2:11])=[N:5]2

Participants

5

Reactant 2

HCID 313Hydrochloric AcidHCID 68827797HCID 68827797, compound

Product 1

HCID 450917081-(Tetrazolo[1,5-b]pyridazin-6-yl)methanamineYield 82%

Reagents, catalysts & solvents 2

HCID 23938PalladiumCatalystHCID 887MethanolSolvent

Procedure

Tetrazolo[1,5-b]pyridazine-6-carbonitrile (228 mg, 1.58 mmol), as prepared in the previous step, was added to a mixture of 10% Pd/C (118 mg), MeOH (8.5 mL), and 12 N HCl (0.54 mL), and was then shaken in a Parr hydrogenation apparatus at 40 psig for 5 h. The mixture was then filtered through Celite, the filter cake was washed with MeOH (2×5 mL), and concentrated to afford 255 mg of the hydrochloride salt of the title compound as an off-white solid (1.29 mmol, 82% yield, assuming dihydrochloride salt). A portion of the salt was neutralized with saturated Na2CO3 and extracted with EtOAc. The organic layer was dried (Na2SO4) and concentrated to afford the title compound (free base). 1H-NMR (300 MHz, CDCl3) δ 8.36 (d, 9.3 Hz, 1H), 7.65 (d, 9.3 Hz, 1H), 4.27 (s, 2H), 1.62 (br s, overlapped with water peak). LC/MS (m/z) [M+1]+ 151.0 (calculated for C5H6N6, 150.1).

Workup

  1. filtrationThe mixture was then filtered through Celite
  2. washthe filter cake was washed with MeOH (2×5 mL)
  3. concentrationconcentrated

Sources & evidence

ORD record
ord-278e1be2a984413dace8e20843ce1345
Source dataset
uspto-grants-2009_06
Patent number
US07550474B2

Reaction notes

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