Potassium Carbonate → 6-(3-Thienylmethoxy)-1,3-benzoxathiol-2-one

A mixture of 6-hydroxy-1,3-benzoxathiol-2-one (15 g) and potassium carbonate (13.8 g) in dimethylformamide (200 mL) is stirred for 20 minutes, and is then treated, dropwise, with 3-chloromethylthiophene (11.8 g). The mixture is stirred at 60° C. for 16 hours. The reaction mixture is then concentrated in vacuo, and partitioned between water (200 mL) and ethyl acetate (200 mL). The aqueous layer is extracted with ethyl acetate (100 mL) and with diethyl ether (100 mL), and the combined aqueous layers are washed with brine, dried over magnesium sulphate, and evaporated to give a yellow solid, which is recrystallised from ethanol (200 mL) to give 6-(3-thienylmethoxy)-1,3-benzoxathiol-2-one (8.9 g), in the form of pale yellow crystals.

1. additionis then treated
2. stirringThe mixture is stirred at 60° C. for 16 hours
3. concentrationThe reaction mixture is then concentrated in vacuo
4. custompartitioned between water (200 mL) and ethyl acetate (200 mL)
5. extractionThe aqueous layer is extracted with ethyl acetate (100 mL) and with diethyl ether (100 mL)
6. washthe combined aqueous layers are washed with brine
7. dry with materialdried over magnesium sulphate
8. customevaporated
9. customto give a yellow solid, which
10. customis recrystallised from ethanol (200 mL)

ORD record

ord-d339c431f09948629813eca16e91aff5

Source dataset

uspto-grants-2001_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06211234B1