N-bromobutanimide → methyl 4-(bromoethynyl)benzoate

HRID 1477233Notes

Reaction equation

HRID 1477233 reaction equation
[C:1]([C:3]1[CH:12]=[CH:11][C:6]([C:7]([O:9][CH3:10])=[O:8])=[CH:5][CH:4]=1)#[CH:2].C1C(=O)N([Br:20])C(=O)C1>CC(C)=O.[N+]([O-])([O-])=O.[Ag+]>[Br:20][C:2]#[C:1][C:3]1[CH:12]=[CH:11][C:6]([C:7]([O:9][CH3:10])=[O:8])=[CH:5][CH:4]=1

Participants

5

Reactant 2

HCID 67184N-bromobutanimideHCID 640163Methyl 4-ethynylbenzoate

Product 1

HCID 10966594methyl 4-(bromoethynyl)benzoateYield 90.4%

Reagents, catalysts & solvents 2

HCID 24470Silver NitrateCatalystHCID 180AcetoneSolvent

Procedure

To a solution of methyl 4-ethynylbenzoate (50 g, 0.31 mol) in acetone (750 mL) was added AgNO3 (5 g, 29.7 mmol) and the reaction mixture was stirred for 1 hr. NBS (61.2 g, 0.34 mol) was added and the reaction mixture was stirred at room temperature for 20 hr, filtered and concentrated under reduced pressure. The residue was diluted in EA, and washed with iced 20% H2SO4. The organic layer was washed with water and brine, dried (Na2SO4), filtered, concentrated under reduced pressure to give a residue, which was recrystallized from MeOH (1 mL/4 g) to yield methyl 4-(bromoethynyl)benzoate (INT-1.4) as an off-yellow solid (67 g, 90%). 1H NMR (400 MHz, CDCl3) δ 7.98 (d, J=8.8 Hz, 2H), 7.51 (d, J=8.8 Hz, 2H), 3.92 (s, 3H).

Workup

  1. stirringthe reaction mixture was stirred at room temperature for 20 hr
  2. filtrationfiltered
  3. concentrationconcentrated under reduced pressure
  4. additionThe residue was diluted in EA
  5. washwashed with iced 20% H2SO4
  6. washThe organic layer was washed with water and brine
  7. dry with materialdried (Na2SO4)
  8. filtrationfiltered
  9. concentrationconcentrated under reduced pressure
  10. customto give a residue, which
  11. customwas recrystallized from MeOH (1 mL/4 g)

Sources & evidence

ORD record
ord-0904ca8ec81a4865b738582cfff55d25
Source dataset
uspto-grants-2016_08
Patent number
US09403758B2

Reaction notes

Loading…