Trimethyl orthoformate → 4-Bromo-2-(1,1-dimethoxyethyl)-7-methoxyfuro[2,3-c]pyridine

HRID 564722Notes

Reaction equation

HRID 564722 reaction equation
[C:1]([C:4]1[O:15][C:7]2=[C:8]([O:13][CH3:14])[N:9]=[CH:10][C:11]([Br:12])=[C:6]2[CH:5]=1)(=[O:3])[CH3:2].[CH3:16][O:17]C(OC)OC.O.[C:24]1(C)C=CC(S(O)(=O)=O)=CC=1>CO>[Br:12][C:11]1[CH:10]=[N:9][C:8]([O:13][CH3:14])=[C:7]2[O:15][C:4]([C:1]([O:17][CH3:16])([O:3][CH3:24])[CH3:2])=[CH:5][C:6]=12

Participants

5

Reactant 3

HCID 9005Trimethyl orthoformateHCID 521998p-Toluenesulfonic acid monohydrateHCID 221127982-Acetyl-4-bromo-7-methoxyfuro[2,3-c]pyridine

Product 1

HCID 221128034-Bromo-2-(1,1-dimethoxyethyl)-7-methoxyfuro[2,3-c]pyridineYield 61%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

A solution of 2-acetyl-4-bromo-7-methoxyfuro[2,3-c]pyridine (1.4 g), trimethylorthoformate (1.1 g) and p-toluenesulfonic acid monohydrate (1.2 g) in dry methanol (50 ml) was heated at reflux for 3 h. The mixture was cooled and the methanol removed in vacuo. The residue was taken up in ethyl acetate (100 ml), washed with saturated sodium bicarbonate solution (50 ml) and brine (50 ml), dried over magnesium sulfate, filtered and the solvent removed in vacuo. Purification by column chromatography on silica eluting with 33% ethyl acetate in hexane gave the title compound (contaminated with 15% 2-acetyl-4-bromo-7-methoxyfuro[2,3-c]pyridine) as a white solid (1.0 g).

Workup

  1. temperatureat reflux for 3 h
  2. temperatureThe mixture was cooled
  3. customthe methanol removed in vacuo
  4. washwashed with saturated sodium bicarbonate solution (50 ml) and brine (50 ml)
  5. dry with materialdried over magnesium sulfate
  6. filtrationfiltered
  7. customthe solvent removed in vacuo
  8. customPurification by column chromatography on silica eluting with 33% ethyl acetate in hexane

Sources & evidence

ORD record
ord-c68f2119a6a34f4cb00333b0869672c6
Source dataset
uspto-grants-2001_01
Patent number
US06169090A

Reaction notes

Loading…