Dimethyl Sulfoxide → tert-Butyl 4-formylpiperidine-1-carboxylate

Temperature

-78 °C

A solution of oxalyl chloride (6 mL, 70 mmol) in dichloromethane (60 mL) at −78° C. was treated dropwise with dimethyl sulfoxide (10 mL, 0.14 mol). After 15 minutes, 1-tert-butoxycarbonyl-4-piperidinemethanol (3.0 g, 14 mmol) was added as a solution in dichloromethane (35 mL). The mixture was stirred at −78° C. for 1 hr, then triethylamine (29 mL, 0.21 mol) was added dropwise. The mixture was warmed to ambient temperature and poured into a saturated ammonium chloride solution (200 mL). The organic layer was separated and the aqueous layer was washed with dichloromethane (75 mL). The organic layers were combined and washed with brine (75 mL); then dried with MgSO4, filtered and concentrated. The residue was redissolved in ethyl acetate-hexanes (1:1) and filtered through Florisil (100-200 mesh). The resulting filtrate was concentrated yielding 3.0 g (100%) of the title aldehyde as a yellow oil; which was used without further purification.

1. temperatureThe mixture was warmed to ambient temperature
2. customThe organic layer was separated
3. washthe aqueous layer was washed with dichloromethane (75 mL)
4. washwashed with brine (75 mL)
5. dry with materialthen dried with MgSO4
6. filtrationfiltered
7. concentrationconcentrated
8. dissolutionThe residue was redissolved in ethyl acetate-hexanes (1:1)
9. filtrationfiltered through Florisil (100-200 mesh)
10. concentrationThe resulting filtrate was concentrated

ORD record

ord-2f7911cab9b04bfd8700c80ee5646fe8

Source dataset

uspto-grants-2003_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06635657B1