Reaktion #4443

Reaktionsgleichung

Ethyl formate

2-benzyl-4-(4-pyridyl)thiazole

tetramethylethylenediamine

n-butyl lithium

→

2-phenyl-2-[4-(4-pyridyl)-2-thiazolyl]acetaldehyde

Ausbeute 39.0%

Lösungsmittel

tetrahydrofuran

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturwarmed to 0° C. for 2 hours
2. 2
   Temperaturcooled to -78° C
3. 3
   workup.STIRRINGto stir at -78° C. for 30 minutes
4. 4
   workup.WAITat 0° C. for one hour
5. 5
   SonstigeThe reaction mixture was quenched with methanol
6. 6
   Einengenconcentrated
7. 7
   Sonstigechromatographed over silica gel
8. 8
   SonstigeRecrystallization from hexane/ethyl acetate

Vorschrift

To a solution of 2-benzyl-4-(4-pyridyl)thiazole (4.00 g, 0.016 mol) and tetramethylethylenediamine (2.5 mL) in dry tetrahydrofuran (35 mL) at -78° C. under nitrogen atmosphere was added dropwise n-butyl lithium (1.6M in hexane, 11.4 mL). The resulting dark mixture was allowed to stir at -78° C. for 15 minutes, warmed to 0° C. for 2 hours, then cooled to -78° C. Ethyl formate (1.47 mL) was added dropwise and the mixture allowed to stir at -78° C. for 30 minutes then at 0° C. for one hour. The reaction mixture was quenched with methanol, concentrated, and chromatographed over silica gel. Recrystallization from hexane/ethyl acetate afforded 2-phenyl-2-[4-(4-pyridyl)-2-thiazolyl]acetaldehyde (1.76 g, 39%). mp. 163°-164° C.

Quelle