Acetonitrile → 2-Fluoro-5-nitropyridine

HRID 3297

Reaction equation

HRID 3297 reaction equation
Cl[C:2]1[CH:7]=[CH:6][C:5]([N+:8]([O-:10])=[O:9])=[CH:4][N:3]=1.[F-:11].[K+].C(#N)C>[P+](C1C=CC=CC=1)(C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1.[Br-].CCOCC>[F:11][C:2]1[CH:7]=[CH:6][C:5]([N+:8]([O-:10])=[O:9])=[CH:4][N:3]=1

Participants

6

Reactant 3

HCID 6342AcetonitrileHCID 783082-Chloro-5-nitropyridineHCID 522689Potassium Fluoride

Product 1

HCID 952642-Fluoro-5-nitropyridine

Reagents, catalysts & solvents 2

HCID 2724163Tetraphenylphosphonium BromideCatalystHCID 3283Diethyl EtherSolvent

Procedure

2-Chloro-5-nitropyridine (100 g, 0.656 mol, Aldrich), KF (84.1 g, 1.448 mol), Ph4PBr (95.3 g, 0.227 mol) and acetonitrile (1.5 L) were combined and heated at reflux until no starting material remained. The volume was reduced to 750 mL, and the mixture was diluted with 2 L of ether, filtered and concentrated. The residue was triturated with hot hexane (5×1 L). The hexane extracts were combined and concentrated to afford 48 g (54%). 1H NMR (CDCl3, 300 MHz) δ7.15 (dd, J=3, 6 Hz, 1H), 8.64 (m, 1H), 9.15 (d, J=1.6 Hz, 1H).

Workup

  1. temperatureheated
  2. temperatureat reflux until no starting material
  3. filtrationfiltered
  4. concentrationconcentrated
  5. customThe residue was triturated with hot hexane (5×1 L)
  6. concentrationconcentrated
  7. customto afford 48 g (54%)

Sources & evidence

ORD record
ord-c3b0e2987bf6463288457f21739f34ea
Source dataset
uspto-grants-1998_03
Patent number
US05733912

Linked notes

Loading…