Reaction #2059

Reaction equation

2-[2,4-dichloro-5-(2-propynyloxy)-phenyl]-2,4-dihydro-5-(3,4-epoxybutyl)-3H-1,2,4-triazol-3-one

potassium carbonate

→

title product

Yield 36.8%

5,6,7,8-tetrahydro-2-[2,4-dichloro-5-(2-propynyloxy)phenyl]-6-hydroxy- 1,2,4-triazolo[4.3-α]pyridin-3(2H)-one

Yield 36.8%

Solvents

acetonitrile

Conditions

Workup

1. 1
   Temperaturewas warmed
2. 2
   Temperatureat reflux for 2h
3. 3
   Filtrationfiltered
4. 4
   OtherThe filtrate was evaporated in vacuo
5. 5
   OtherThe crude product was purified by flash chromatography over silica gel
6. 6
   Washeluting with a 95:5 v
7. 7
   workup.ADDITIONv mixture of dichloromethane and methanol

Procedure

A mixture of 500 mg (1.41 mmol) of 2-[2,4-dichloro-5-(2-propynyloxy)-phenyl]-2,4-dihydro-5-(3,4-epoxybutyl)-3H-1,2,4-triazol-3-one and 563 mg (4.08 mmol) of potassium carbonate in 20 mL of acetonitrile was warmed at reflux for 2h. The mixture was cooled to room temperature and filtered. The filtrate was evaporated in vacuo. The crude product was purified by flash chromatography over silica gel, eluting with a 95:5 v:v mixture of dichloromethane and methanol to give 184 mg of the title product of Step 4 as a pale yellow foam, 1H NMR (CDCl3, 400 MHz) δ 7.5 (s,1H), 7.15 (s,1H), 4.8 (s,2H), 4.45 (broad t,1H), 3.8 (m,2H), 3.0 (m,1H), 2.8 (m,1H), 2.6 (s,1H), 2.2 (s,1H), 2.15 (m,1H), 1.95 (m,1H).

Source