p-Toluenesulfonic acid → HCID 178428357, compound

HRID 1896462Notes

Reaction equation

HRID 1896462 reaction equation
[CH3:1][C:2]1[CH:7]=[CH:6][N:5]=[C:4]([NH2:8])[C:3]=1[N+:9]([O-])=O.[H][H].[C:14]1([C:20](OC)(OC)OC)[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=1.CC1C=CC(S(O)(=O)=O)=CC=1.C([O-])(O)=O.[Na+]>CO.[Ni].CCCCCC.O>[CH3:1][C:2]1[CH:7]=[CH:6][N:5]=[C:4]2[NH:8][C:20]([C:14]3[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=3)=[N:9][C:3]=12

Participants

10

Reactant 5

HCID 6101p-Toluenesulfonic acidHCID 69720Trimethyl orthobeznoateHCID 2431662-Amino-4-methyl-3-nitropyridineHCID 516892Sodium BicarbonateHCID 178418361HCID 178418361, compound

Product 1

HCID 178428357HCID 178428357, compoundYield 40%

Reagents, catalysts & solvents 4

HCID 935NickelCatalystHCID 887MethanolSolventHCID 962WaterSolventHCID 8058HexaneSolvent

Conditions

Temperature
165 °C

Procedure

Raney Ni (1.5 g) is added to a mixture of commercially available nitrogen-containing 4-methyl-3-nitropyridin-2-amine x220 (4.0 g, 26.1 mmol) in methanol (150 ml), and the obtained reaction mixture is hydrogenated in the Parr apparatus at the hydrogen pressure 3 atm until the total conversion of compound x220 is attained for approximately 1.5-2 h. The catalyst is separated by filtration, the filtrate is washed with methanol, and the alcohol solution is evaporated to dryness. The residue is dissolved in sulfolane (10 ml), then PhC(OMe)3 (5.7 g, 1.2 eq, 31.3 mmol) and PTSA (0.3 g) are added, and an air reflux condenser is mounted. The apparatus is argon-blown, and the obtained reaction mixture is heated to 165° C. under vigorous stirring for 10 h. Water (100 ml), saturated aqueous NaHCO3 (5 ml), and hexane (50 ml) are added to the reaction mixture. The obtained suspension is stirred for 5 min, and the residue is separated by filtration. The residue is washed with water (50 ml) and hexane (100 ml), and vacuum-dried over P2O5 to a constant weight at 45° C. to give 7-methyl-2-phenyl-3H-imidazo[4,5-b]pyridine x221 (2.2 g).

Workup

  1. customthe obtained reaction mixture
  2. customThe catalyst is separated by filtration
  3. washthe filtrate is washed with methanol
  4. customthe alcohol solution is evaporated to dryness
  5. dissolutionThe residue is dissolved in sulfolane (10 ml)
  6. temperaturean air reflux condenser
  7. customthe obtained reaction mixture
  8. stirringThe obtained suspension is stirred for 5 min
  9. customthe residue is separated by filtration
  10. washThe residue is washed with water (50 ml) and hexane (100 ml)
  11. dry with materialvacuum-dried over P2O5 to a constant weight at 45° C.

Sources & evidence

ORD record
ord-a529a106018c499fad7fa07abdf5329c
Source dataset
uspto-grants-2013_08
Patent number
US08518943B2

Reaction notes

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