Hydrochloric Acid → 459-86-9

HRID 2258176Notes

Reaction equation

HRID 2258176 reaction equation
C(=O)(O)O.[NH2:5][NH:6][C:7]([NH2:9])=[NH:8].[CH:10](O)([CH3:12])[CH3:11].Cl.COC(OC)(C)C=O>O>[CH3:11]/[C:10](/[CH:12]=[N:5]/[N:6]=[C:7]([NH2:9])[NH2:8])=[N:5]\[N:6]=[C:7]([NH2:9])[NH2:8]

Participants

6

Reactant 4

HCID 313Hydrochloric Acid2×HCID 3776Isopropanol2×HCID 75681812,2-DimethoxypropanalHCID 178513185HCID 178513185, compound2×

Product 1

HCID 5351154459-86-9Yield 47%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent2×

Conditions

Temperature
32 °C

Procedure

Aminoguanidine bicarbonate (Aldrich 98.5%) was slurried in DI water at 35°-40° C. for about 30 minutes, the suspension was filtered to remove diaminoguanidine and other impurities amounting to about 1% w/w. 505 g, 3.8 mol of the filtered aminoguanidine bicarbonate was suspended in 200 g DI water and 300 g (156 mL) isopropanol to give a heavy, but stirrable mixture. Concentrated HCl (376 g, 37.8%) was cautiously added dropwise over a 1.5 hr period to prevent excessive foaming (Note 1). The mixture stirred readily after 5% of the HCl had been added. The reaction was endothermic and the temperature was maintained at between 19° C. and 28° C. At the end of the addition a clear colorless solution was obtained (Note 2). It was warmed to 32° C. and stirred for 20 minutes (Note 3). The methyl glyoxal dimethylacetal (212 g, 1.79 mol) (Fluka, 98%) was next added over 1.5 hours at a temperature of 30°-35° ) (Note 4). The suspension was stirred overnight at ambient temperature. The next morning isopropanol (2.0 kg) was added over 15-20 minutes. The suspension was cooled to about 10° C. and stirring was continued for 1.5 hours. The solids were collected by filtration and rinsed with 2×200 mL isopropanol. After drying overnight in a vacuum oven at 30°-35° C., 463 g (47%) of the crude MGBG was obtained. TLC [acetone 90, water 5, NH4OH 5]; HPLC (ETI~0.79%); nmr (dmsod6).

Workup

  1. filtrationthe suspension was filtered
  2. customto remove diaminoguanidine and other impurities amounting to about 1% w/w
  3. additionhad been added
  4. temperaturethe temperature was maintained at between 19° C. and 28° C
  5. additionAt the end of the addition a clear colorless solution
  6. customwas obtained (Note 2)
  7. stirringThe suspension was stirred overnight at ambient temperature
  8. temperatureThe suspension was cooled to about 10° C.
  9. stirringstirring
  10. waitwas continued for 1.5 hours
  11. filtrationThe solids were collected by filtration
  12. washrinsed with 2×200 mL isopropanol
  13. customAfter drying overnight in a vacuum oven at 30°-35° C.

Sources & evidence

ORD record
ord-e172cfb11016447b87a41c04173f317b
Source dataset
uspto-grants-1997_08
Patent number
US05659083

Reaction notes

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