p-Toluenesulfonic acid → Oxazolo(4,5-b)pyridine

HRID 1444580Notes

Reaction equation

HRID 1444580 reaction equation
[NH2:1][C:2]1[C:7]([OH:8])=[CH:6][CH:5]=[CH:4][N:3]=1.[CH2:9](OC(OCC)OCC)C.C1(C)C=CC(S(O)(=O)=O)=CC=1>>[O:8]1[C:7]2[C:2](=[N:3][CH:4]=[CH:5][CH:6]=2)[N:1]=[CH:9]1

Participants

4

Reactant 3

HCID 6101p-Toluenesulfonic acidHCID 281142-Amino-3-HydroxypyridineHCID 31214Ethyl orthoformate

Product 1

HCID 10103159Oxazolo(4,5-b)pyridine

Conditions

Temperature
140 °C

Procedure

A mixture of 2-amino-3-hydroxypyridine (25 g, 227 mmol), triethylorthoformate (75 mL) and p-toluenesulfonic acid (61 mg) was heated at 140° C. for 8 h. Excess triethylorthoformate was removed under vacuum. The product was crystallized from ethyl acetate to yield 22.5 g of oxazolo[4,5-b]pyridine.

Workup

  1. customExcess triethylorthoformate was removed under vacuum
  2. customThe product was crystallized from ethyl acetate

Sources & evidence

ORD record
ord-87d1074a14bd4b028205d5bf7d16b128
Source dataset
uspto-grants-2010_02
Patent number
US07662849B2

Reaction notes

Loading…