tert-butyl N-[(1R,2S)-2-(hydroxymethyl)cyclopentyl]carbamate

Conditions: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of ((1R,2S)-2-hydroxymethyl-cyclopentyl)-carbamic acid tert-butyl ester (1.6 g, 7.43 mmol) in THF (40 ml) was added potassium tert-butoxide (3.34 g, 29.7 mmol, 4.0 equiv.) at room temperature. After stirring for 1 h at 60° C. the reaction was allowed to warm up to room temperature and after workup with Ethyl acetate/water, drying and concentration in vacuo, the crude material mixture was adsorbed on silica and chromatographed over a prepacked silica column (50 g, 50% to 100% EtOAc in Heptane gradient) to yield 950 mg (91%) of the title compound as a white solid, which was directly used in the next step. to warm up to room temperature after workup with Ethyl acetate/water, drying concentration in vacuo chromatographed over a prepacked silica column (50 g, 50% to 100% EtOAc in Heptane gradient)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a well stirred suspension of 0.94 g (24.7 mmol, 2 equiv.) of LiAlH4 in 30 ml of THF at 0° C. was added dropwise at 0° C. a solution of (1S,2R)-methyl 2-(tert-butoxycarbonylamino)-cyclopentanecarboxylate (CAS: 592503-55-4) (3.0 g, 12.3 mmol) (gas evolution, lightly exotherm). After 15 minutes at 0° C. the reaction mixture was allowed to warm up to room temperature and was stirred for 2 h. The mixture was cooled to 0° C. and water was added dropwise. The precipitated inorganic salts were filtered through Celite and were washed with ethyl acetate. The filtrate was evaporated and the residue was purified by column chromatography on silica gel eluting with a 0% to 50% ethyl acetate in heptane gradient to yield 1.99 g (75%) of the title compound as a crystalline white solid which was directly used in the next step. was stirred for 2 h The mixture was cooled to 0° C. The precipitated inorganic salts were filtered through Celite were washed with ethyl acetate The filtrate was evaporated the residue was purified by column chromatography on silica gel eluting with a 0% to 50% ethyl acetate in heptane gradient