Cesium carbonate → Tert-butyl 2-isopropyl-[1,2,4]triazolo[1,5-a]pyridin-7-ylcarbamate

HRID 1802196Notes

Reaction equation

HRID 1802196 reaction equation
Br[C:2]1[CH:7]=[CH:6][N:5]2[N:8]=[C:9]([CH:11]([CH3:13])[CH3:12])[N:10]=[C:4]2[CH:3]=1.[C:14](=[O:21])([O:16][C:17]([CH3:20])([CH3:19])[CH3:18])[NH2:15].C(=O)([O-])[O-].[Cs+].[Cs+]>O1CCOCC1.C1C=CC(/C=C/C(/C=C/C2C=CC=CC=2)=O)=CC=1.C1C=CC(/C=C/C(/C=C/C2C=CC=CC=2)=O)=CC=1.C1C=CC(/C=C/C(/C=C/C2C=CC=CC=2)=O)=CC=1.[Pd].[Pd].C1(P(C2C=CC=CC=2)C2C3OC4C(=CC=CC=4P(C4C=CC=CC=4)C4C=CC=CC=4)C(C)(C)C=3C=CC=2)C=CC=CC=1>[CH:11]([C:9]1[N:10]=[C:4]2[CH:3]=[C:2]([NH:15][C:14](=[O:21])[O:16][C:17]([CH3:20])([CH3:19])[CH3:18])[CH:7]=[CH:6][N:5]2[N:8]=1)([CH3:13])[CH3:12]

Participants

7

Reactant 3

HCID 10796Cesium carbonateHCID 77922tert-Butyl carbamateHCID 677766607-Bromo-2-(propan-2-yl)[1,2,4]triazolo[1,5-a]pyridine

Product 1

HCID 67774335Tert-butyl 2-isopropyl-[1,2,4]triazolo[1,5-a]pyridin-7-ylcarbamateYield 93.4%

Reagents, catalysts & solvents 3

HCID 6360441,1'-(9,9-Dimethyl-9H-xanthene-4,5-diyl)bis(1,1-diphenylphosphine)CatalystHCID 9811564Bis(dibenzylideneacetone)palladiumCatalystHCID 312751,4-DioxaneSolvent

Procedure

To an argon purged solution of 7-bromo-2-isopropyl-[1,2,4]triazolo[1,5-a]pyridine (378 mg, 1.57 mmol) in dioxane (10 ml) are added tert-butyl carbamate (221 mg, 1.89 mmol), cesium carbonate (718 mg, 2.2 mmol), tris(dibenzylideneacetone)dipalladium(0) (28.8 mg, 31.5 μmol) and 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (36.4 mg, 63.0 μmol). The resulting mixture is refluxed for 2.5 days (weekend) under argon atmosphere. The crude material is loaded on silicagel and purified by flash chromatography on a 20 g silica column using heptane/ethyl acetate 20-70% as eluent affording tert-butyl 2-isopropyl-[1,2,4]triazolo[1,5-a]pyridin-7-ylcarbamate (405 mg, 93.1%) as a light yellow solid. Mp.: 215-8° C. MS: m/z=277.1 (M+H+).

Workup

  1. temperatureThe resulting mixture is refluxed for 2.5 days (weekend) under argon atmosphere
  2. custompurified by flash chromatography on a 20 g silica column

Sources & evidence

ORD record
ord-f6592142ded14cdebe99619981527764
Source dataset
uspto-grants-2013_01
Patent number
US08349824B2

Reaction notes

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