Reaktion #358256

Reaktionsgleichung

2,6-dichloropyridine

Lithium diisopropylamine

2-Chlorobenzaldehyde

→

(2-chloro-phenyl)-(2,6-dichloro-pyridin-3-yl)-methanol

Ausbeute 62.5%

Lösungsmittel

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGthe reaction mixture was stirred for 30 minutes at −78° C
2. 2
   SonstigeThe reaction was quenched by addition of 80 mL saturated ammonium chloride and 200 mL of water
3. 3
   Extraktionthe aqueous mixture was extracted once with 300 mL of EtOAc
4. 4
   WaschenThe comnbined organic phase was washed with saturated brine and water
5. 5
   Trocknenwas dried over MgSO4
6. 6
   SonstigeSolvent was removed under reduced pressure
7. 7
   Sonstigethe residue was purified by FLASH column chromatography

Vorschrift

2,6-dichloropyridine (10.0 g, 67.6 mmol) was dissolved in 220 mL of dry THF and the reaction mixture was cooled to −78° C. under argon. Lithium diisopropylamine (60 mL, 118 mmol, 2M in heptanes) was added to the reaction mixture over 12 minutes via cannula, and the reaction mixture was stirred for 15 minutes at −78° C. 2-Chlorobenzaldehyde (16 mL, 141.96 mmol) was added dropwise, and the reaction mixture was stirred for 30 minutes at −78° C. The reaction was quenched by addition of 80 mL saturated ammonium chloride and 200 mL of water, and the aqueous mixture was extracted once with 300 mL of EtOAc and a second time with 250 mL of EtOAc. The comnbined organic phase was washed with saturated brine and water and was dried over MgSO4. Solvent was removed under reduced pressure and the residue was purified by FLASH column chromatography using 5%-20% EtOAc/Hexanes to yield 12.2 g of (2-chloro-phenyl)-(2,6-dichloro-pyridin-3-yl)-methanol as a yellow oil. Mass Spec. M+H=290.

Quelle