Reaktion #7755

Reaktionsgleichung

2,2-Dimethyl-propionic acid 1-[2-(4-fluorophenyl)acetyl]-2-(methylsulfany-pyrimidine-4-carbonyl)-pyrazolidin-4-yl ester

NaH

→

desired product

Ausbeute 30.0%

2,2-dimethyl-propionic acid 6-(4-fluorophenyl)-7-(2-methylsulfanyl-pyrimidin-4-yl)-5-oxo-2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-2-yl ester

Ausbeute 30.0%

Lösungsmittel

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe reaction is quenched with NH4Cl (sat. aq.) (1 mL)
2. 2
   Einengenconcentrated in vacuo
3. 3
   workup.ADDITIONThe residue is diluted with tetrahydrofuran (50 mL)
4. 4
   Filtrationthe mixture filtered through Celite
5. 5
   EinengenThe filtrate is concentrated in vacuo
6. 6
   Sonstigeto give an orange oil
7. 7
   SonstigeThe crude product is purified over silica (100% ethyl acetate to 5% to 10% to 20% methyl alcohol/ethyl acetate)

Vorschrift

2,2-Dimethyl-propionic acid 1-[2-(4-fluorophenyl)acetyl]-2-(methylsulfany-pyrimidine-4-carbonyl)-pyrazolidin-4-yl ester, 33, (300 mg, 0.651 mmol) is dissolved in THF (6 mL). This solution is then added dropwise via cannula to a suspension of NaH (29 mg of a 60% dispersion in mineral oil, 0.716 mmol) at −30° C. The reaction is allowed to gradually warm to 0° C. over 3 hours. The reaction is quenched with NH4Cl (sat. aq.) (1 mL). The mixture is stirred at room temperature, then concentrated in vacuo. The residue is diluted with tetrahydrofuran (50 mL) and the mixture filtered through Celite. The filtrate is concentrated in vacuo to give an orange oil. The crude product is purified over silica (100% ethyl acetate to 5% to 10% to 20% methyl alcohol/ethyl acetate) to afford 87 mg (30% yield) of the desired product as a yellow solid.

Quelle