Boron tribromide → alpha-[2-(Diisopropylamino)ethyl]-alpha-(4-hydroxyphenyl)-2-pyridineacetamide

HRID 1905778Notes

Reaction equation

HRID 1905778 reaction equation
[CH:1]([N:4]([CH:25]([CH3:27])[CH3:26])[CH2:5][CH2:6][C:7]([C:17]1[CH:22]=[CH:21][C:20]([O:23]C)=[CH:19][CH:18]=1)([C:11]1[CH:16]=[CH:15][CH:14]=[CH:13][N:12]=1)[C:8]([NH2:10])=[O:9])([CH3:3])[CH3:2].B(Br)(Br)Br>C(Cl)Cl>[CH:25]([N:4]([CH:1]([CH3:3])[CH3:2])[CH2:5][CH2:6][C:7]([C:17]1[CH:22]=[CH:21][C:20]([OH:23])=[CH:19][CH:18]=1)([C:11]1[CH:16]=[CH:15][CH:14]=[CH:13][N:12]=1)[C:8]([NH2:10])=[O:9])([CH3:27])[CH3:26]

Participants

4

Reactant 2

HCID 25134Boron tribromideHCID 20215410HCID 20215410, compound

Product 1

HCID 20215409alpha-[2-(Diisopropylamino)ethyl]-alpha-(4-hydroxyphenyl)-2-pyridineacetamide

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent2×

Procedure

A solution of 7.32 grams (g) [0.02 moles (mol)] of α-[2-(diisopropylamino)ethyl]-α-(4-methoxyphenyl)-2-pyridineacetamide [Karim, supra] in 250 milliliters (mL) of methylene chloride (CH2Cl2) was cooled to -78° C. while stirring under an inert atmosphere. To this was added dropwise 19.85 g (0.08 mol) of boron tribromide dissolved in 50 mL of CH2Cl2. The resulting brown suspension was allowed to warm to room temperature, then was heated at reflux for 1 hour. It was cooled to -10° C., and excess boron tribromide destroyed by the addition of 150 mL of 10% sodium hydroxide (NaOH) solution. The organic phase was separated and extracted with n-butanol. Evaporation left a residue which was purified by chromatography on silica gel eluting with 60:10:1 (v/v/v) CHCl3 :MeOH:conc. ammonium hydroxide. This gave 4.8 g of the phenol as a pale tan solid. A sample was recrystallized from toluene to give a solid, mp 148°-151° C.

Workup

  1. temperaturewas heated
  2. temperatureat reflux for 1 hour
  3. temperatureIt was cooled to -10° C.
  4. customexcess boron tribromide destroyed by the addition of 150 mL of 10% sodium hydroxide (NaOH) solution
  5. customThe organic phase was separated
  6. extractionextracted with n-butanol
  7. customEvaporation
  8. waitleft a residue which
  9. customwas purified by chromatography on silica gel eluting with 60:10:1 (v/v/v) CHCl3
  10. customA sample was recrystallized from toluene
  11. customto give a solid, mp 148°-151° C.

Sources & evidence

ORD record
ord-2eb00b2ce0c64a8ab2391cfd31562f58
Source dataset
uspto-grants-1987_03
Patent number
US04647668

Reaction notes

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