Dimethyl Sulfoxide → HCID 59201564, compound

Temperature

-65 °C

A solution of DMSO (0.82 g, 10.47 mmol) in 10 mL of dry CH2Cl2, under protection of N2, was cooled to −78° C., followed by the slow, dropwise addition of oxalyl chloride (0.664 g, 5.23 mmol). After addition the mixture was stirred 2 hr at −65° C., then the solution of (S)-tert-butyl 1-(4-hydroxycyclohexyl)-3-(N-methyl-N-(benzyloxycarbonyl)amino)propan-2-ylcarbamate (1.1 g, 2.62 mmol) was added dropwise. After addition, the mixture was stirred 3 hr at −30° C. The reaction was quenched with Et3N (4 mL) and stirred 10 min, then saturated NaHCO3 (10 mL) was added. The aqueous layer was extracted 3 times with CH2Cl2 (3×20 mL). The CH2Cl2 layer was washed with 10% citric acid solution (20 mL), followed by saturated NaHCO3, brine, then dried over Na2SO4. After filtration, solvent removal gave crude product (1 g), which was purified by preparative TLC to give (S)-tert-butyl 1-(N-methyl-N-(benzyloxycarbonyl)amino)-3-(4-oxocyclohexyl)propan-2-ylcarbamate (500 mg, 1.2 mmol).

1. additionAfter addition the mixture
2. additionAfter addition
3. stirringthe mixture was stirred 3 hr at −30° C
4. customThe reaction was quenched with Et3N (4 mL)
5. stirringstirred 10 min
6. additionsaturated NaHCO3 (10 mL) was added
7. extractionThe aqueous layer was extracted 3 times with CH2Cl2 (3×20 mL)
8. washThe CH2Cl2 layer was washed with 10% citric acid solution (20 mL)
9. dry with materialdried over Na2SO4
10. filtrationAfter filtration, solvent removal
11. customgave crude product (1 g), which
12. customwas purified by preparative TLC

ORD record

ord-38ae103994514255ba8e825e7dc70508

Source dataset

uspto-grants-2013_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08487108B2