Boron tribromide → 5-Formyl-2,3-dihydroxybenzonitrile

HRID 727403

Reaction equation

HRID 727403 reaction equation
[CH:1]([C:3]1[CH:4]=[C:5]([C:8]([OH:13])=[C:9]([O:11]C)[CH:10]=1)[C:6]#[N:7])=[O:2].B(Br)(Br)Br>ClCCl>[CH:1]([C:3]1[CH:4]=[C:5]([C:8]([OH:13])=[C:9]([OH:11])[CH:10]=1)[C:6]#[N:7])=[O:2]

Participants

4

Reactant 2

HCID 25134Boron tribromideHCID 18359065Benzonitrile, 5-formyl-2-hydroxy-3-methoxy-

Product 1

HCID 152925835-Formyl-2,3-dihydroxybenzonitrileYield 72.4%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent2×

Conditions

Temperature
0 °C

Procedure

18 g of the product of Step A and 400 ml of dichloromethane were mixed together under nitrogen and the mixture was cooled to 0° C. 150 ml of a molar solution of boron tribromide in dichloromethane were added and the mixture stood for one night at ambient temperature. It was concentrated, cooled again to 0° C. and 250 ml of a normal solution of hydrochloric acid were added. The crystallized product was separated out, washed with water, dried then crystallized from an isopropanol-water mixture (1-2) to obtain 12 g of the expected product.

Workup

  1. waitthe mixture stood for one night at ambient temperature
  2. concentrationIt was concentrated
  3. temperaturecooled again to 0° C.
  4. addition250 ml of a normal solution of hydrochloric acid were added
  5. customThe crystallized product was separated out
  6. washwashed with water
  7. customdried
  8. customthen crystallized from an isopropanol-water mixture (1-2)

Sources & evidence

ORD record
ord-77c34083bc7a48cca1fde12f03f524f0
Source dataset
uspto-grants-1998_01
Patent number
US05712266

Linked notes

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