Trichloroacetonitrile → Ethyl 2-ethyl-4-(2,2,2-trichloro-1-iminoethoxy)cyclopentanecarboxylate

To ethyl 2-ethyl-4-hydroxycyclopentanecarboxylate (3.52 g, 18.9 mmol, Preparation #P.1) in DCM (21 mL) at about 0° C. was added aqueous potassium hydroxide (50%, 21 mL, 189 mmol), tetrabutylammonium hydrogen sulfate (0.64 g, 1.891 mmol) and 2,2,2-trichloroacetonitrile (9.5 mL, 95 mmol). The reaction mixture was allowed to warm to ambient temperature and stirred at ambient temperature for about 14 h. The layers were separated and the aqueous layer was extracted with DCM (4×60 mL). The combined organic layers were washed with water (2×50 mL), brine (60 mL), dried over anhydrous MgSO4, filtered and concd under reduced pressure. The material was purified by silica gel chromatography eluting with a gradient of 15-50% EtOAc in heptane to afford ethyl 2-ethyl-4-(2,2,2-trichloro-1-iminoethoxy)cyclopentanecarboxylate (2.80 g, 45%) as a colorless oil: LC/MS (Table 1, Method b) Rt=2.91 min; MS m/z: 330 (M+H)+.

1. customThe layers were separated
2. extractionthe aqueous layer was extracted with DCM (4×60 mL)
3. washThe combined organic layers were washed with water (2×50 mL), brine (60 mL)
4. dry with materialdried over anhydrous MgSO4
5. filtrationfiltered
6. customThe material was purified by silica gel chromatography
7. washeluting with a gradient of 15-50% EtOAc in heptane

ORD record

ord-bedb48e9ce7f4d20967dc8bd7e18035a

Source dataset

uspto-grants-2013_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08426411B2