1-tert-Butyl-4-piperidone → 4-(Bromomethylene)-1-tert-butylpiperidine

To a solution of (bromomethyl)triphenylphosphonium bromide (1.52 g, 3.48 mmol) in dry THF (15 mL) at −78° C. was added potassium tert-butoxide (3.5 mL, 1.0M) slowly. After stirring 20 minutes, 1-tert-butylpiperidin-4-one (COMPOUND PPA-1) (595 mg, 3.83 mmol) in THF (2 mL) was added, and the reaction mixture was warmed up to rt slowly over 2 h. The reaction mixture was quenched with brine, and it was extracted with CH2Cl2. The combined extracts were dried over Na2SO4 then concentrated in vacuo. The crude material was purified by flash chromatography eluting first with hexane then gradually increasing to 5% acetone/hexane to give the title compound. 1H NMR (CDCl3, 500 MHz): δ 5.85 (s, 1H); 2.56 (m, 4H); 2.43 (t, J=5.6 Hz, 2H); 2.28 (t, J=5.6 Hz, 2H); 1.08 (s, 9H).

1. customThe reaction mixture was quenched with brine, and it
2. extractionwas extracted with CH2Cl2
3. dry with materialThe combined extracts were dried over Na2SO4
4. concentrationthen concentrated in vacuo
5. customThe crude material was purified by flash chromatography
6. washeluting first with hexane
7. temperaturethen gradually increasing to 5% acetone/hexane

ORD-Eintrag

ord-f18a93c702b94c3e98826f3451ca491e

Quelldatensatz

uspto-grants-2004_10

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US06809199B2