4-OXOTETRAHYDROTHIOPHENE-2,3-DICARBOXYLIC ACID DIMETHYL ESTER synthesis

5synthesis methods

Product Name:4-OXOTETRAHYDROTHIOPHENE-2,3-DICARBOXYLIC ACID DIMETHYL ESTER
CAS Number:38293-63-9
Molecular formula:C8H10O5S
Molecular Weight:218.23

624-48-6 Synthesis

624-48-6
359 suppliers
$7.00/25g

2365-48-2 Synthesis

2365-48-2
334 suppliers
$19.00/25g

4-OXOTETRAHYDROTHIOPHENE-2,3-DICARBOXYLIC ACID DIMETHYL ESTER

38293-63-9
32 suppliers
$175.00/500mg

Yield:38293-63-9 22.7 g

Reaction Conditions:

with piperidine;sodium methylate in tetrahydrofuran;methanol at 55; for 3 h;Inert atmosphere;Reflux;

Steps:

1 Reference Example 1 Dimethyl 4-oxothiolane-2,3-dicarboxylate

To a reaction mixture of methylthioglycolate (15.0 g), tetrahydrofuran (45 g), piperidine (0.361 g), a solution of dimethyl maleate (21.4 g) in tetrahydrofuran (30 g) was added at room temperature. To the reaction mixture was added a methanol solution (43 g) of 20% sodium methoxide at 55 ° C. under a nitrogen atmosphere. The reaction mixture was stirred under reflux for 3 hours. Diisopropyl ether (105 g) and acetic acid (0.85 g) were added to the reaction mixture at 45 to 50 ° C. and then cooled. The suspension was filtered to obtain wet crystals (43.3 g) of sodium salt of 4-oxothiolane-2,3-dicarbonate. The wet crystals were added to a mixture of 85% phosphoric acid (9.8 g), water (20 g) and ethyl acetate (150 g) at room temperature and the aqueous layer was removed. The obtained organic layer was washed with 10% brine and then dried over anhydrous magnesium sulfate. After removal of the drying agent by filtration, the filtrate was concentrated under reduced pressure to give the title compound (22.7 g).

References:

JP6268093,2018,B2 Location in patent:Paragraph 0023