4-Methoxybenzenesulfonyl chloride → AC1M6VJW

Participants

Reaction Steps

Cis-4-hydroxy-D-proline (9.0 g, 68.6 mmol) is dissolved in 100 mL mixture of water and p-dioxane (1:1) and then triethyl amine (19.1 mL, 137.3 mmol), 4-methoxyphenylsulfonyl chloride (15.6 g, 75.5 mmol), and 4-dimethylaminopyridine (0.86 g, 6.86 mmol) are added. The solution is stirred at room temperature overnight. The reaction mixture is washed with sodium bicarbonate and extracted once with ether. The water layer is acidified with 1N HCl until pH~2 is achieved and then the solution is extracted three times with ethyl acetate. The ethyl acetate layers are washed with ammonium chloride, and dried (MsSO4), filtered and evaporated to give the crude acid. Cl+ MS: m/z (rel intensity) 302.0(M+ +H, 100).

Provenance & Evidence