Hexamethyldisilazane → 2-(3-Bromo-4-methanesulfonyl-phenyl)-3-cyclopentyl-propionamide

Temperature

0 °C

A mixture of 2-(3-bromo-4-methanesulfonyl-phenyl)-3-cyclopentyl-propionic acid (400 mg, 1.07 mmol) in methylene chloride (4 mL) cooled to 0° C. was treated with N,N-dimethylformamide (2 drops) followed by oxalyl chloride (100 μL, 1.18 mmol). The reaction mixture was stirred at 0° C. for 10 min and then stirred at 25° C. for 1 h. The resulting reaction mixture was then treated dropwise with 1,1,1,3,3,3-hexamethyldisilazane (680 μL, 3.21 mmol) and subsequently stirred at 25° C. for 15 h. The reaction mixture was then diluted with methylene chloride (20 mL) and methanol (20 mL). The organic layer was washed with a 5% aqueous sulfuric acid solution (1×40 mL) and a saturated aqueous sodium chloride solution. The organic layer was dried over magnesium sulfate, filtered, and concentrated in vacuo to afford 2-(3-bromo-4-methanesulfonyl-phenyl)-3-cyclopentyl-propionamide (271 mg, 68%) as a white foam. The white foam was used without further purification: mp 60-63° C.; EI-HRMS m/e calcd for C15H20BrNO3S (M+) 373.0347, found 373.0348.

1. stirringstirred at 25° C. for 1 h
2. customThe resulting reaction mixture
3. stirringsubsequently stirred at 25° C. for 15 h
4. washThe organic layer was washed with a 5% aqueous sulfuric acid solution (1×40 mL)
5. dry with materialThe organic layer was dried over magnesium sulfate
6. filtrationfiltered
7. concentrationconcentrated in vacuo

ORD record

ord-1ab19e6de41d4e9db2c3a7f2ba69d13c

Source dataset

uspto-grants-2003_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06528543B1