反应详情

A solution of 5-chlorosulfonyl-2-hydroxybenzoic acid (0.52 g, 2.0 mmol, Matrix Scientific) in tetrahydrofuran (10 mL) was treated with pyrrolidine (1.5 g, 21 mmol) and refluxed for 2 h. This was cooled and poured into dilute aqueous hydrochloric acid and extracted into dichloromethane (2×50 mL). The combined extracts were washed with brine, dried over magnesium sulfate, filtered, and concentrated to give a solid. This was triturated with ether to give 2-hydroxy-5-(pyrrolidine-1-sulfonyl)benzoic acid as a solid. It was then converted to 2-ethoxy-5-(pyrrolidine-1-sulfonyl)benzoic acid ethyl ester In a manner analogous to the method described in example 33.

1. temperaturerefluxed for 2 h
2. temperatureThis was cooled
3. extractionextracted into dichloromethane (2×50 mL)
4. washThe combined extracts were washed with brine
5. dry with materialdried over magnesium sulfate
6. filtrationfiltered
7. concentrationconcentrated
8. customto give a solid
9. customThis was triturated with ether