Methanol → 3-bromo-5H,6H,7H-cyclopenta[b]pyridin-7-one

HRID 1526610Notes

Reaction equation

HRID 1526610 reaction equation
C(=[C:8]1/[CH2:9][CH2:10][C:11]2[C:12]/1=[N:13][CH:14]=[C:15]([Br:17])[CH:16]=2)/C1C=CC=CC=1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.C[OH:38]>C(Cl)Cl>[Br:17][C:15]1[CH:16]=[C:11]2[CH2:10][CH2:9][C:8](=[O:38])[C:12]2=[N:13][CH:14]=1

Participants

5

Reactant 3

HCID 887MethanolHCID 11776TriphenylphosphineHCID 90415449(E)-7-benzylidene-3-bromo-6,7-dihydro-5H-cyclopenta[b]pyridine

Product 1

HCID 468641583-bromo-5H,6H,7H-cyclopenta[b]pyridin-7-oneYield 96%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

A solution of (E)-7-benzylidene-3-bromo-6,7-dihydro-5H-cyclopenta[b]pyridine (1.61 g, 5.63 mmol) in MeOH (75 mL) and DCM (75 mL) was cooled to −78° C. and a stream of ozone in oxygen was bubbled through the solution for 10 min until the solution turned light blue. Oxygen was pass through the solution for 10 min until the solution turned colorless. Triphenylphosphine (3.63 g, 13.8 mmol) was added and the reaction mixture was allowed to warm to room temperature. The reaction mixture was stirred at room temperature for 1.5 h and then concentrated under reduced pressure. The residue was purified by flash column chromatography on silica gel (80 g, 30% to 70% EtOAc in heptane) to give 3-bromo-5H-cyclopenta[b]pyridin-7(6H)-one (1.14 g, 5.38 mmol, 96% yield) as a yellow solid. MS m/z=211.9 [M+H]+. Calculated for C8H6BrNO 211.0.

Workup

  1. customa stream of ozone in oxygen was bubbled through the solution for 10 min until the solution
  2. customfor 10 min
  3. concentrationconcentrated under reduced pressure
  4. customThe residue was purified by flash column chromatography on silica gel (80 g, 30% to 70% EtOAc in heptane)

Sources & evidence

ORD record
ord-85f7ac6c2f7f4f9bb4092c505142fffc
Source dataset
uspto-grants-2015_07
Patent number
US09085576B2

Reaction notes

Loading…