Reaktion #318882

Reaktionsgleichung

triethylamine

chlorosulfonyl isocyanate

terguride

→

3-(2-cyano-6-methyl-8α-ergolinyl)-1,1-diethylurea

Ausbeute 31.0%

Lösungsmittel

acetonitrile

acetonitrile

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe ice bath is removed
2. 2
   workup.ADDITIONThen the mixture is diluted with methylene chloride
3. 3
   Extraktionextracted with 1N sodium hydroxide solution
4. 4
   Extraktionthe water phase is once more extracted
5. 5
   TrocknenThe combined organic phases are dried with sodium sulfate
6. 6
   Sonstigeevaporated
7. 7
   SonstigeThe residue is chromatographed on silica gel with a mixture of methylene chloride and methanol

Vorschrift

680 mg of terguride (2 mmol) is dissolved in 120 ml of acetonitrile and 5.5 ml of triethylamine and, under ice cooling, a solution of 3.5 ml of chlorosulfonyl isocyanate in 40 ml of acetonitrile is added dropwise thereto under an argon atmosphere. The ice bath is removed and the mixture allowed to stand for two days at room temperature. To facilitate isolation of the polar by-products, the mixture is combined with 20 ml of diethylamine and stirred for three hours at room temperature. Then the mixture is diluted with methylene chloride, extracted with 1N sodium hydroxide solution, and the water phase is once more extracted. The combined organic phases are dried with sodium sulfate and evaporated. The residue is chromatographed on silica gel with a mixture of methylene chloride and methanol, thus isolating 229 mg (31% of theory) of crude 3-(2-cyano-6-methyl-8α-ergolinyl)-1,1-diethylurea. After crystallizing from ethyl acetate, 92 mg is obtained as the pure compound.

Quelle