Potassium Carbonate → 1-(3-Isopropoxybenzyl)-2-methylpiperidin-4-one

Temperatur

-20 °C

In an alternative preparation, AlCl3 (15 g, 0.11 mole) was added to a 3-necked flask equipped with a jacketed addition funnel, flushed with argon and cooled in an ice bath. Crotonyl chloride (21 g, 200 mmol) was added dropwise while keeping the temperature of the reaction below 15° C. The resulting light yellow solution was stirred for 15 min before the ice bath was replaced with an ethyleneglycol/dry ice bath and the solution cooled to −20° C. Vinylsilane (21.1 ml, 220 mmol) was added dropwise from the ice-cooled jacketed addition funnel keeping the temperature of the reaction below −20° C. The reaction was stirred for 3 hr and then added quickly to a slurry of 200 mL saturated aqueous sodium/potassium tartrate solution, 200 g K2CO3, 300 mL ice and 500 mL ether. The slurry was stirred vigorously for 30 min then filtered through celite. The organic layer was separated, dried over Na2SO4, filtered and carefully concentrated. The oil was dissolved in 200 mL CH3CN and added dropwise to a cooled (0° C.) suspension of 3-(isopropoxy)benzylamine (30 g, 180 mmol) in a mixture of 2M aq NaHCO3 (100 mL) and CH3CN (30 mL). The reaction was stirred at rt overnight and partitioned between water and EtOAc. The organic layer was dried over Na2SO4, filtered and concentrated. The resulting oil was chromatographed on silica eluting with 0-50% EtOAc/Hexanes.

1. additionwas added to a 3-necked flask
2. customequipped with a jacketed addition funnel
3. customflushed with argon
4. temperaturecooled in an ice bath
5. customthe temperature of the reaction below 15° C
6. customwas replaced with an ethyleneglycol/dry ice bath
7. temperaturecooled
8. additionaddition funnel
9. customthe temperature of the reaction below −20° C
10. stirringThe slurry was stirred vigorously for 30 min
11. filtrationthen filtered through celite
12. customThe organic layer was separated
13. dry with materialdried over Na2SO4
14. filtrationfiltered
15. concentrationcarefully concentrated
16. dissolutionThe oil was dissolved in 200 mL CH3CN
17. additionadded dropwise to
18. temperaturea cooled
19. stirringThe reaction was stirred at rt overnight
20. custompartitioned between water and EtOAc
21. dry with materialThe organic layer was dried over Na2SO4
22. filtrationfiltered
23. concentrationconcentrated
24. customThe resulting oil was chromatographed on silica eluting with 0-50% EtOAc/Hexanes

ORD-Eintrag

ord-55bb8e3ff3db436ba34dadcae77a7210

Quelldatensatz

uspto-grants-2012_07

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08211904B2