Reacción #168919

Ecuación de reacción

dry ice

4,5-dimethoxy-2-(1-methyl-2-phenyl-ethyl)-benzaldehyde

2,2,6,6-tetramethyl piperidine

n-Butyllithium

2,4-Dimethoxypyrimidine

→

[4,5-dimethoxy-2-(1-methyl-2-phenyl-ethyl)-phenyl]-(2,4-dimethoxy-pyrimidin-5-yl)-methanol

Rendimiento 52.0%

Disolventes

THF

THF

Condiciones de reacción

Tratamiento posterior

1. 1
   workup.ADDITIONwas added drop-wise over 5 minutes
2. 2
   workup.STIRRINGAfter stirring for 1 hour the solution
3. 3
   Temperaturawas warmed to room temperature
4. 4
   Otroquenched by the slow addition of 50 mL 10% NH4Cl
5. 5
   workup.ADDITIONAfter 100 mL of H2O was added the mixture
6. 6
   Extracciónwas extracted with ethyl acetate
7. 7
   Lavadowashed with H2O
8. 8
   Lavadowashed with brine
9. 9
   SecadoThe combined organics were dried over Na2SO4
10. 10
    Filtraciónfiltered
11. 11
    Concentraciónconcentrated in vacuo
12. 12
    Otroto give an orange oil
13. 13
    OtroPurification via flash chromatography (3:2 hexane/ethyl acetate)

Procedimiento

Freshly distilled 2,2,6,6-tetramethyl piperidine (0.85 mL, 5.0 mmol) was dissolved in 20 mL THF and cooled to 0° C. n-Butyllithium (2.0 mL, 2.5 M in hexanes) was added drop-wise over 5 minutes and the mixture was allowed to stir for 30 minutes and then cooled to −78° C. 2,4-Dimethoxypyrimidine (0.353 g, 2.52 mmol) was added drop-wise over 5 min. After 45 min the solution was transferred via a dry ice cooled cannula to a solution of 4,5-dimethoxy-2-(1-methyl-2-phenyl-ethyl)-benzaldehyde (0.717 g, 2.52 mmol) in 20 mL THF at −78° C. After stirring for 1 hour the solution was warmed to room temperature and quenched by the slow addition of 50 mL 10% NH4Cl. After 100 mL of H2O was added the mixture was extracted with ethyl acetate, washed with H2O and washed with brine. The combined organics were dried over Na2SO4, filtered and concentrated in vacuo to give an orange oil. Purification via flash chromatography (3:2 hexane/ethyl acetate) afforded [4,5-dimethoxy-2-(1-methyl-2-phenyl-ethyl)-phenyl]-(2,4-dimethoxy-pyrimidin-5-yl)-methanol (0.551 g, 52%) as a clear oil.

Fuente