2-Amino-6-bromopyridine → 6-(6-aminopyrid-2-yl)-N-phenylimidazo[1,2-a]pyridine-2-carboxamide

HRID 1878446Notes

Reaction equation

HRID 1878446 reaction equation
C[Sn](C)(C)[C:3]1[CH:4]=[CH:5][C:6]2[N:7]([CH:9]=[C:10]([C:12]([NH:14][C:15]3[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=3)=[O:13])[N:11]=2)[CH:8]=1.Br[C:24]1[N:29]=[C:28]([NH2:30])[CH:27]=[CH:26][CH:25]=1>C1C=CC([P]([Pd]([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)[P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1.CN(C)C=O>[NH2:30][C:28]1[N:29]=[C:24]([C:3]2[CH:4]=[CH:5][C:6]3[N:7]([CH:9]=[C:10]([C:12]([NH:14][C:15]4[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=4)=[O:13])[N:11]=3)[CH:8]=2)[CH:25]=[CH:26][CH:27]=1

Participants

5

Reactant 2

HCID 3008092-Amino-6-bromopyridineHCID 441359416-trimethylstannyl-N-phenylimidazo[1,2-a]pyridine-2-carboxamide2×

Product 1

HCID 687783156-(6-aminopyrid-2-yl)-N-phenylimidazo[1,2-a]pyridine-2-carboxamideYield 75.7%

Reagents, catalysts & solvents 2

HCID 178418397HCID 178418397, compoundCatalystHCID 6228DimethylformamideSolvent

Procedure

236 mg of 6-trimethylstannyl-N-phenylimidazo[1,2-a]pyridine-2-carboxamide (Intermediate 4), 413 mg of 6-bromopyrid-2-ylamine, 95 mg of tetrakis(triphenylphosphine)palladium and 4 mL of N,N-dimethylformamide are placed in a microwave tube. The reaction mixture is heated for 45 minutes in a microwave machine set at 150° C. and concentrated to dryness. The residue is chromatographed on a silica cartridge, eluting with a mixture of dichloromethane and ethyl acetate. The fractions containing the expected product are combined and evaporated to dryness under reduced pressure to give 147 mg of 6-(6-aminopyrid-2-yl)-N-phenylimidazo[1,2-a]pyridine-2-carboxamide in the form of a yellow solid, which product is taken up in a mixture of dioxane and methanol and treated with 112 μL of a 4 M solution of hydrogen chloride in dioxane. After stirring for 1 hour at room temperature, the precipitate is filtered off by suction, washed with dioxane and dried to give 156 mg of 6-(6-aminopyrid-2-yl)-N-phenylimidazo[1,2-a]pyridine-2-carboxamide hydrochloride (1:1) in the form of a pale yellow solid.

Workup

  1. temperatureThe reaction mixture is heated for 45 minutes in a microwave machine
  2. customset at 150° C.
  3. concentrationconcentrated to dryness
  4. customThe residue is chromatographed on a silica cartridge
  5. washeluting with a mixture of dichloromethane and ethyl acetate
  6. additionThe fractions containing the expected product
  7. customevaporated to dryness under reduced pressure

Sources & evidence

ORD record
ord-a3c3fec360b84df6aefcefaa2a09f26b
Source dataset
uspto-grants-2012_11
Patent number
US08314109B2

Reaction notes

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