Di-tert-butyl azodicarboxylate → Di-tert-butyl 1-{3-[(4,4-difluoropiperidin-1-yl)methyl]phenyl}hydrazine-1,2-dicarboxylate

Temperatur

-78 °C

n-Butyllithium (1.6 M in hexanes, 4.5 mL, 7.28 mmol) was added dropwise to a stirred solution of Intermediate 12a (1.98 g, 6.82 mmol) in dry THF (15 mL) at −78° C. under nitrogen. The mixture was stirred at −78° C. for 10 min, then di-tert-butyl azodicarboxylate (1.73 g, 7.51 mmol) was added in one portion. The mixture was stirred at −78° C. for 20 min, then allowed to warm to RT over 20 min. The mixture was then partitioned between saturated ammonium chloride solution (15 mL) and ethyl acetate (3×20 mL). The combined organic extracts were washed with brine (20 mL) and dried (Na2SO4). The solvent was evaporated and the residue purified by FCC, eluting with 0-100% EtOAc in pentane, to give the title compound as a pale yellow oil (1.30 g, 43%). LCMS (Method 1): Rt 2.54 min, m/z 442 [MH+].

1. stirringThe mixture was stirred at −78° C. for 20 min
2. temperatureto warm to RT over 20 min
3. customThe mixture was then partitioned between saturated ammonium chloride solution (15 mL) and ethyl acetate (3×20 mL)
4. washThe combined organic extracts were washed with brine (20 mL)
5. dry with materialdried (Na2SO4)
6. customThe solvent was evaporated
7. customthe residue purified by FCC
8. washeluting with 0-100% EtOAc in pentane

ORD-Eintrag

ord-d5c37a94dee74a31a8211dddb17e72ce

Quelldatensatz

uspto-grants-2015_05

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US09029373B2