Reaktion #8370

Reaktionsgleichung

Hydrochloric acid

lithium borohydride

6-(3-quinolin-4-yl-5,6-dihydro-4H-pyrrolo[1,2-b]pyrazol-2-yl)pyridine-2-carboxylic acid methyl ester

lithium borohydride

→

title compound

Ausbeute 58.4%

[6-(3-Quinolin-4-yl-5,6-dihydro-4H-pyrrolo[1,2-b]pyrazol-2-yl)-pyridin-2-yl]-methanol

Ausbeute 58.4%

Lösungsmittel

methanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGthe resulting mixture stirred at room temperature for 16 h
2. 2
   Einengenthe resulting mixture concentrated in vacuo
3. 3
   Sonstigepartitioned between ethyl acetate (150 mL) and saturated potassium carbonate (150 mL)
4. 4
   WaschenThe organic portion is washed with brine (150 mL)
5. 5
   Trocknendried (magnesium sulfate)
6. 6
   Einengena concentrated in vacuo
7. 7
   SonstigeThe residue is precipitated from ethyl acetate with hexanes

Vorschrift

To a solution of 6-(3-quinolin-4-yl-5,6-dihydro-4H-pyrrolo[1,2-b]pyrazol-2-yl)pyridine-2-carboxylic acid methyl ester (0.550 g, 1.48 mmol) in methanol (20 mL) is added lithium borohydride (35.5 mg, 1.63 mmol). The mixture is stirred 1 h, additional lithium borohydride (35.5 mg, 1.63 mmol) added, and the resulting mixture stirred at room temperature for 16 h. 4 N Hydrochloric acid (3 mL) is added slowly and the resulting mixture concentrated in vacuo. The residue is taken up in methanol (10 mL) and partitioned between ethyl acetate (150 mL) and saturated potassium carbonate (150 mL). The organic portion is washed with brine (150 mL), dried (magnesium sulfate), and a concentrated in vacuo. The residue is precipitated from ethyl acetate with hexanes to yield 296 mg (58%) of the title compound.

Quelle