反应详情

Step AS (2): To a solution of ethyl 2-(4-chlorobutyl)-1,3-dithiane-2-carboxylate (550 mg, 1.94 mmol) in THF (5 mL) was added a solution of LiOH (233 mg, 9.72 mmol) in water (2 mL). Methanol (2 mL) was added and the resulting mixture was stirred at rt for 2 d. The solvents were removed in vacuo. Aqueous 1 N HCl (50 mL) was added. The mixture was extracted with EtOAc (80 mL). The organic layer was washed with water, dried over sodium sulfate, filter, and concentrated in vacuo to afford 2-(4-chlorobutyl)-1,3-dithiane-2-carboxylic acid (400 mg, 1.57 mmol, 81% yield). LC-MS (M+H)+ 253.0. The crude product was used for subsequent chemistry without purification.

1. customThe solvents were removed in vacuo
2. additionAqueous 1 N HCl (50 mL) was added
3. extractionThe mixture was extracted with EtOAc (80 mL)
4. washThe organic layer was washed with water
5. dry with materialdried over sodium sulfate
6. filtrationfilter
7. concentrationconcentrated in vacuo