Triethylborane → HCID 68904762, compound

HRID 1890937

Reaction equation

HRID 1890937 reaction equation
C(=O)([O-])[O-].[Na+].[Na+].Cl[C:8]1[C:17]2[C:12](=[CH:13][CH:14]=[C:15]([O:18][CH3:19])[CH:16]=2)[N:11]=[CH:10][CH:9]=1.[CH2:20](B(CC)CC)[CH3:21].CCCCCC>[Pd].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.C1(C)C=CC=CC=1>[CH2:20]([C:8]1[C:17]2[C:12](=[CH:13][CH:14]=[C:15]([O:18][CH3:19])[CH:16]=2)[N:11]=[CH:10][CH:9]=1)[CH3:21]

Participants

8

Reactant 4

HCID 7357Triethylborane2×HCID 8058HexaneHCID 10340Sodium CarbonateHCID 2283484-Chloro-6-methoxyquinoline

Product 1

HCID 68904762HCID 68904762, compound

Reagents, catalysts & solvents 3

HCID 23938PalladiumCatalystHCID 178418397HCID 178418397, compoundCatalystHCID 1140TolueneSolvent

Conditions

Temperature
90 °C

Procedure

A mixture of toluene (17 mL) and 2 M aqueous sodium carbonate (5 mL) was degassed by bubbling nitrogen for 20 minutes. To the mixture was added 4-chloro-6-methoxy-quinoline (500 mg, 2.58 mmol) and tetrakis(triphenylphosphine)palladium(0) (90 mg, 0.0774 mmol), followed by 1 M triethylborane solution in hexane (15.5 mL, 15.5 mmol). The reaction mixture was stirred at 90° C. for 4 days, periodically adding more palladium catalyst (270 mg total) and triethylborane solution (30 mL total) to drive the reaction. The reaction mixture was cooled to room temperature and partitioned between water and ethyl acetate. The organic layer was separated, dried over sodium sulfate, filtered, and adsorbed on silica gel. Purification by flash chromatography using a gradient of 0-70% ethyl acetate/hexane afforded 579 mg of impure 4-ethyl-6-methoxy-quinoline as a waxy off white solid. The solid was treated with concentrated sulfuric acid (6 mL) and water (4 mL). The reaction mixture was stirred at reflux for 5 h and poured onto ice. Ammonium hydroxide was added until pH 9 and the aqueous layer was extracted with ethyl acetate (2×). Combined organics were adsorbed on silica gel. Purification by flash chromatography using a gradient of 0-80% ethyl acetate/hexane afforded 195 mg of 4-ethyl-quinolin-6-ol as an off white solid (44% yield): 1H NMR (DMSO-d6) δ 1.30 (t, 3H), 2.96 (q, 2H), 7.25 (d, 1H), 7.28 (m, 2H), 7.86 (d, 1H), 8.56 (d, 1H), 9.98 (broad s, 1H); MS (m/z) 174 [M+H]+.

Workup

  1. customwas degassed
  2. customby bubbling nitrogen for 20 minutes
  3. customthe reaction
  4. temperatureThe reaction mixture was cooled to room temperature
  5. custompartitioned between water and ethyl acetate
  6. customThe organic layer was separated
  7. dry with materialdried over sodium sulfate
  8. filtrationfiltered
  9. customPurification by flash chromatography

Sources & evidence

ORD record
ord-f7b0733dc7b249f3afa9adec906b8374
Source dataset
uspto-grants-2013_08
Patent number
US08507489B2

Linked notes

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