Reaktion #554373

Reaktionsgleichung

5-{[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methylene}-2-thioxo-4-thiazolidinone

diethyl 2,6-dimethyl-1,4-dihydro-3,5-pyridinedicarboxylate

ethyl acetate

→

desired title product

Ausbeute 56.9%

5-[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl]-2-thioxo-4-thiazolidinone

Ausbeute 56.9%

Lösungsmittel

toluene

toluene

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeForty grams of silica gel 60 (finer than 230 mesh) previously dried in vacuo at 50° C. for 7 hours
2. 2
   workup.ADDITIONwere added to the reaction
3. 3
   TemperaturThe reaction was heated
4. 4
   Temperaturat reflux for 18 hours
5. 5
   Filtrationfiltered hot
6. 6
   SonstigeThe filtrate was evaporated to dryness
7. 7
   workup.DISSOLUTIONThe residue was dissolved in 500 ml of ethyl acetate
8. 8
   Waschenwashed 5 times each with 400 ml of 1N hydrochloric acid
9. 9
   Trocknendried over sodium sulfate
10. 10
    Filtrationfiltered
11. 11
    Sonstigeevaporated in vacuo
12. 12
    Sonstigeto provide a yellow solid

Vorschrift

Under a nitrogen atmosphere, 13.98 g of 5-{[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methylene}-2-thioxo-4-thiazolidinone, 13.17 g of diethyl 2,6-dimethyl-1,4-dihydro-3,5-pyridinedicarboxylate and 600 ml of toluene were stirred to effect solution. Forty grams of silica gel 60 (finer than 230 mesh) previously dried in vacuo at 50° C. for 7 hours were added to the reaction. The reaction was heated at reflux for 18 hours and filtered hot. The filtrate was evaporated to dryness. The residue was dissolved in 500 ml of ethyl acetate, washed 5 times each with 400 ml of 1N hydrochloric acid, dried over sodium sulfate, filtered, and evaporated in vacuo to provide a yellow solid. Chromatography over silica gel eluting with 2.5% ethyl acetate in toluene provided 8.0 g of the desired title product, m.p. 178-179° C.

Quelle