Chlorotrimethylsilane → 1-Methyl-4-trimethylsilanyloxy-1,2,3,6-tetrahydro-pyridine

Temperature

110 °C

To a stirred solution of 1-methyl-piperidin-4-one (6.0 g, 53 mmol, 6.52 mL) and Et3N (14.16 g, 140 mmol, 19.5 mL) in 1,4-dioxane (20 mL) was added chlorotrimethylsilane (7.6 g, 70 mmol, 8.88 mL) drop wise during 30 min. The resultant reaction mixture was slowly heated to reflux at 110° C., stirred at the same temperature for 24 h, an additional amount of chlorotrimethylsilane (4.44 mL), heated for 24 h (take aliquot of it and run 1H NMR), cooled to room temp, filtered off the solid, solid was washed with n-pentane. The filtrate was concentrated on rotavaporator, and then diluted with n-pentane and filtered off the solid. The resultant solution was concentrated on rotavaporator followed by high vacuum furnished the 1-methyl-4-trimethylsilanyloxy-1,2,3,6-tetrahydro-pyridine (9.68 g, 1H NMR showed about 10:1 ratio of silylenolether and the starting material). The crude product was as such used in the next step without further purification.

1. customThe resultant reaction mixture
2. temperaturewas slowly heated
3. temperaturecooled to room temp
4. filtrationfiltered off the solid, solid
5. washwas washed with n-pentane
6. concentrationThe filtrate was concentrated on rotavaporator
7. additiondiluted with n-pentane
8. filtrationfiltered off the solid
9. concentrationThe resultant solution was concentrated on rotavaporator

ORD record

ord-d7cb342d249e42f39b74c1ef366bf1ba

Source dataset

uspto-grants-2014_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08829030B2