(1R,3s,5S)-methyl 6-oxabicyclo[3.1.0]hexane-3-carboxylate → Methyl (1S,3R,4R)-3-ethyl-4-hydroxy-cyclopentanecarboxylate

Temperature

-25 °C

To a suspension of copper(I) iodide (4.95 g, 26.0 mmol) in 50 ml ether at −25° C. was added ethyllithium (1.7M, 30.6 ml, 52.0 mmol) dropwise. The solution was stirred for 1 hr at −25° C. followed by dropwise addition of an ether solution (50 ml) of methyl (1S,5R)-6-oxabicyclo[3.1.0]hexane-3-carboxylate (1.848 g, 13 mmol) maintaining at −25° C. The reaction was allowed to warm to rt until TLC showed complete reaction. Cooled in ice and quenched with NH4Cl (sat)(5 ml) and stirred for 10 minutes. Filtered thru celite and washed with ether (3×10 ml) and the combined filtrates were washed with brine and dryed over sodium sulfate. Silica gel chromatagraphy on a 25 g Biotage SNAP column with 10-50% MTBE/Hexane afforded title compound. 1H NMR (500 MHz, CDCl3) δ 0.96 (t, J=7.3 Hz, 3H), δ 1.24-1.48 (m, 2H), δ 1.54-1.77 (m, 3H), δ 1.83-1.90 (m, 1H), δ 2.12-2.29 (m, 2H), δ 3.02 (m, 1H), δ 3.69 (s, 3H), δ 3.98 (m, 1H)

1. temperaturemaintaining at −25° C
2. temperatureto warm to rt until TLC
3. customreaction
4. temperatureCooled in ice
5. customquenched with NH4Cl (sat)(5 ml)
6. stirringstirred for 10 minutes
7. filtrationFiltered thru celite
8. washwashed with ether (3×10 ml)
9. washthe combined filtrates were washed with brine

ORD record

ord-0f7362d7102341bf9a5e3867fd45a0d4

Source dataset

uspto-grants-2012_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08119806B2