Dimethyl Sulfoxide → tert-butyl N-[(2S)-1-oxo-3-phenylpropan-2-yl]carbamate

Temperature

-60 °C

A solution of 2.8 ml (40 mmol) of dry dimethylsulfoxide in 150 ml of dry dichloromethane was cooled under nitrogen atmosphere in a dry ice/chloroform bath (ca. -60° C.). In a separate flask, a 2M solution of oxalyl chloride in dichloromethane (15 ml, 30 mmol) was precooled to -60° C. and then added via cannula. After 10 min, a solution of 5 g (20 mmol) of N-((t-butyloxy)carbonyl)-phenylalaninol in 30 ml of dry dichloromethane was added via cannula. The resulting solution was stirred at -60° C. for 45 min, and was subsequently treated via syringe with 11 ml (80 mmol) of dry triethylamine. After being stirred for an additional 15 min at -60° C., the solution was quenched by addition of 10% aqueous citric acid, then immediately poured into a rapidly stirred mixture of 200 ml of 1:1 hexane:ether and 100 ml of 10% aqueous citric acid. The reaction flask was rinsed with ether which was added to the above mixture. The mixture was poured into a separatory funnel and the layers were sequentially with dilute layer was washed sequentially with dilute aqueous sodium bicarbonate and saturated brine, dried over MgSO4, and concentrated in vacuo to provide the crude desired compound.

1. additionadded via cannula
2. stirringAfter being stirred for an additional 15 min at -60° C.
3. customthe solution was quenched by addition of 10% aqueous citric acid
4. additionimmediately poured into a rapidly stirred mixture of 200 ml of 1:1 hexane
5. washThe reaction flask was rinsed with ether which
6. additionwas added to the above mixture
7. additionThe mixture was poured into a separatory funnel
8. washwas washed sequentially with dilute aqueous sodium bicarbonate and saturated brine
9. dry with materialdried over MgSO4
10. concentrationconcentrated in vacuo

ORD record

ord-b383a813efb64980ac1897b32bb4c034

Source dataset

uspto-grants-1997_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05670675