Реакция #465999

Уравнение реакции

triethylamine

4-benzoyloxy-5,8-dimethyl-1,1-dioxo-1,2,3,4-tetrahydro-1λ6-thiochromene-6-carboxylic acid

oxalyl chloride

cyclohexanedione

→

3-Oxo-1-cyclohexenyl 4-benzoyloxy-5,8-dimethyl-1,1-dioxo-1,2,3,4-tetrahydro-1λ6-thiochromene-6-carboxylate

Растворители

methylene chloride

Условия реакции

Обработка

1. 1
   Температураunder reflux for 3.5 h
2. 2
   Другоеa rotary evaporator
3. 3
   Другоеwas taken up in 100 ml of methylene chloride and, at 0° C.
4. 4
   Концентрированиеsubsequently concentrated
5. 5
   Другоеa rotary evaporator
6. 6
   Другоеthe residue was purified by chromatography (silica gel, ethyl acetate: hexane=1:1)

Методика

0.80 g (2.1 mmol) of 4-benzoyloxy-5,8-dimethyl-1,1-dioxo-1,2,3,4-tetrahydro-1λ6-thiochromene-6-carboxylic acid in 30 ml of methylene chloride was admixed with 2 drops of N,N-dimethylformamide and 1.69 g (13.3 mmol) of oxalyl chloride, and the mixture was boiled under reflux for 3.5 h. The solvents were subsequently stripped off using a rotary evaporator, and the residue was taken up in 100 ml of methylene chloride and, at 0° C., admixed with 0.25 g (2.2 mmol) of cyclohexanedione and 0.44 g (7.4 mmol) of triethylamine. The mixture was stirred at room temperature for 4 h and subsequently concentrated using a rotary evaporator, and the residue was purified by chromatography (silica gel, ethyl acetate: hexane=1:1).

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