Hydrogen Peroxide → HCID 13567777, compound

HRID 280199Notes

Reaction equation

HRID 280199 reaction equation
Br[C:2]1[CH:3]=[C:4]2[CH2:11][CH2:10][CH:9]([C:12]3[CH:17]=[CH:16][C:15]([Cl:18])=[C:14]([Cl:19])[CH:13]=3)[O:8][C:5]2=[N:6][CH:7]=1.OO.C(OCC)(=[O:24])C.CCCCCC>O>[Cl:19][C:14]1[CH:13]=[C:12]([CH:9]2[O:8][C:5]3=[N:6][CH:7]=[C:2]([OH:24])[CH:3]=[C:4]3[CH2:11][CH2:10]2)[CH:17]=[CH:16][C:15]=1[Cl:18]

Participants

5

Reactant 3

HCID 784Hydrogen PeroxideHCID 128207Mdl 20646HCID 21226206Ethyl acetate hexane

Product 1

HCID 13567777HCID 13567777, compound

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Conditions

Temperature
-75 °C

Procedure

6-Bromo-2-(3,4-dichlorophenyl)-3,4-dihydro-2H-pyrano[2,3-b]pyridine (1.5 g) was converted to the corresponding lithio intermediate according to the procedure described in Example 23 and then quenched at -90° C. with 1.3 ml of tri-n-butyl borate. The resulting dark solution was stirred at -75° C. for 2 hours and then allowed to warm to 0° C. The mixture was then acidified with 3N hydrochloric acid, the organic phase was separated, and the aqueous layer was extracted with ether. The combined organic layers were concentrated to give a light brown, tacky solid. To this material was added 25 ml of 30% hydrogen peroxide and the resulting mixture was warmed at 60° C. for 30 minutes. The mixture was then cooled and diluted with 75 ml of water and the resulting mixture was extracted with two 50-ml portions of methylene chloride. The methylene chloride extracts were combined, washed with aqueous saturated sodium chloride solution, dried over sodium sulfate and concentrated to give a yellow solid. Column chromatography (silica gel, 3% ethyl acetate/hexane) gave 2-(3,4-dichlorophenyl)-3,4-dihydro-6-hydroxy-2H-pyrano[2,3-b]pyridine melting at about 218°-219° C.

Workup

  1. customquenched at -90° C. with 1.3 ml of tri-n-butyl borate
  2. temperatureto warm to 0° C
  3. customthe organic phase was separated
  4. extractionthe aqueous layer was extracted with ether
  5. concentrationThe combined organic layers were concentrated
  6. customto give a light brown, tacky solid
  7. temperaturethe resulting mixture was warmed at 60° C. for 30 minutes
  8. temperatureThe mixture was then cooled
  9. extractionthe resulting mixture was extracted with two 50-ml portions of methylene chloride
  10. washwashed with aqueous saturated sodium chloride solution
  11. dry with materialdried over sodium sulfate
  12. concentrationconcentrated
  13. customto give a yellow solid

Sources & evidence

ORD record
ord-8722652a4c934cca89d90e535909430b
Source dataset
uspto-grants-1986_05
Patent number
US04588733

Reaction notes

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