反应详情

To a stirred mixture of 5.44 grams (0.02 mole) of 3-[(4-bromo-2-emthylphenyl)amino)-3oxopropanoic acid prepared in Example V (Compound No. 97) and 2.31 grams (0.02 mole) of thiophenol in approximately 100 milliliters of dry tetrahydrofuran in an oven-dried reaction flask was fed a solution of 4.13 grams (0.02 mole) of 1,3-dicyclohexylcarbodiimlde in about 25 milliliters of dry tetrahydrofuran, while cooling the reaction mixture in an ice-water bath. On completing the feed the ice bath was removed and the mixture stirred for about one hour following which the precipitated 1,3-dicyclohexylurea by-product (2.5 grams) was removed by filtration. Vacuum stripping the filtrate gave a solid which was recrystallized from acetone to give a compound, melting point 184° C.-187° C., which proved to be 1-(3-[(4-bromo2-methylphenyl)amino]-3-oxopropanoyl)-1,3-dicyclohexylurea. The filtrate from this was concentrated and flash chromatographed (7:3 hexane:ethylacetate, silica column) to give 2.83 grams (0.008 mole) of S-phenyl 3-[(4-bromo-2-methylphenyl)amino]-3-oxopropanethioate having a melting point of 133° C.-135° C. Elemental analysis of the product indicated the following:

1. temperaturewhile cooling the reaction mixture in an ice-water bath
2. customwas removed
3. customwas removed by filtration
4. customgave a solid which
5. customwas recrystallized from acetone
6. customto give a compound, melting point 184° C.-187° C., which
7. concentrationThe filtrate from this was concentrated
8. customflash chromatographed (7:3 hexane:ethylacetate, silica column)