Dicyclohexylcarbodiimide → HCID 178477304, compound

Participants

Reaction Steps

0.51 Gram (1.7 mmol) of 4-ethylthio-5-methyl-6-carboxythiochroman-1,1-dioxide was dissolved in 5 ml of t-amyl alcohol, and 0.22 g (2.0 mmol, 1.2 eq.) of 1-ethyl-5-hydroxypyrazole and 0.42 g (2.0 mmol, 1.2 eq.) of N,N'-dicyclohexylcarbodiimide were added. The mixture was stirred at room temperature for 3 hours, and then 0.18 g (1.3 mmol) of potassium carbonate was added. The mixture was heated at 80° C. for 8 hours. After the completion of the reaction, the solvent was distilled off. The remaining oil was dissolved in ethyl acetate and product was extracted with a 5 wt % sodium hydrogencarbonate aqueous solution. 2N Hydrochloric acid was added to the resultant aqueous solution to adjust a pH of 1, and the mixture was extracted with ethyl acetate. An organic layer was washed with a saturated sodium chloride aqueous solution and dried over anhydrous sodium sulfate, and the solvent was distilled off to give 0.5 g (75%) of 4-ethylthio-5-methyl-6-(1-ethyl-5-hydroxypyrazol-4-yl)carbonylthiochroman-1,1-dioxide.

Provenance & Evidence