Methane → methyl (2R,4S)-1-(2-chloroacetyl)-4-hydroxypyrrolidine-2-carboxylate

To a suspension of Example 17A (100 g, 0.55 mol, 1 equivalent) in benzene (2.5 L), chloroacetyl chloride (62.4 g, 0.50 mol, 1 equivalent) was added dropwise at 20-25° C. The reaction mixture was refluxed for 3 hours. Then charcoal (2 g) was added, and the mixture was hot filtered through diatomaceous earth. The filtrate was concentrated under reduced pressure to get a solid. To this crude material, methyl tert-butyl ether (500 mL) was added and stirred for 30 minutes. The solid was collected by filtration, and the wet cake was dried in a vacuum tray dryer for 5 hours at about 50° C. to afford the title compound. 1H NMR (300 MHz, DMSO-d6) δ ppm 2.06-2.15 (m, 1H), 2.31-2.39 (m, 1H), 3.64 (d, 1H, J=11.1 Hz), 3.76 (s, 3H), 3.76-3.86 (m, 2H), 4.09 (s, 2H), 4.6-4.65 (m, 2H).

1. temperatureThe reaction mixture was refluxed for 3 hours
2. filtrationthe mixture was hot filtered through diatomaceous earth
3. concentrationThe filtrate was concentrated under reduced pressure
4. customto get a solid
5. filtrationThe solid was collected by filtration
6. customthe wet cake was dried in a vacuum tray dryer for 5 hours at about 50° C.

ORD-Eintrag

ord-4474444c62134b40a050862150fb7316

Quelldatensatz

uspto-grants-2014_02

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08648074B2