Reaktion #798377

Reaktionsgleichung

Intermediate 74b

4-Iodo-1H-pyrazole-3-carboxylic acid ethyl ester

caesium carbonate

2-(2-bromoethoxy)tetrahydro-2H-pyran

→

title compound

Ausbeute 39.0%

4-Iodo-1-[2-(tetrahydro-pyran-2-yloxy)-ethyl]-1H-pyrazole-3-carboxylic acid ethyl ester

Ausbeute 39.0%

Lösungsmittel

acetonitrile

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe mixture was evaporated in vacuo
2. 2
   Sonstigethe residue was partitioned between EtOAc and water
3. 3
   ExtraktionThe aqueous layer was then extracted with EtOAc (2×)
4. 4
   WaschenThe combined organic layers were washed with saturated aqueous sodium bicarbonate solution and brine
5. 5
   Trocknendried (Na2SO4)
6. 6
   Filtrationfiltered
7. 7
   Sonstigeevaporated in vacuo
8. 8
   SonstigeThe residue was purified by FCC
9. 9
   Sonstigeisolating the

Vorschrift

A suspension of Intermediate 74b (2.72 g, 10.2 mmol) in acetonitrile (27 mL) was treated with caesium carbonate (5.0 g, 15.3 mmol) then 2-(2-bromoethoxy)tetrahydro-2H-pyran (1.70 mL, 11.2 mmol) and the mixture was stirred at 60° C. for 3.5 h. The mixture was evaporated in vacuo and the residue was partitioned between EtOAc and water. The aqueous layer was then extracted with EtOAc (2×). The combined organic layers were washed with saturated aqueous sodium bicarbonate solution and brine, dried (Na2SO4), filtered and evaporated in vacuo. The residue was purified by FCC, using 0-50% EtOAc in cyclohexane, isolating the lower running spot to give the title compound as a colourless glass (1.57 g, 39%). LCMS (Method 3): Rt 3.67 min, m/z 417 [M+Na+].

Quelle