반응 #165661

반응 방정식

sulfur

tetrahydro-4H-pyran-4-one

pyrrolidine

p-toluenesulfonic acid monohydrate

cyanamide

→

title compound

6,7-dihydro-4H-pyrano[4,3-d][1,3]thiazol-2-amine

용매

cyclohexane

methanol

반응 조건

후처리

1. 1
   온도The reaction mixture was refluxed for 3 hours with a Dean-Stark trap
2. 2
   온도cooled
3. 3
   농축concentrated
4. 4
   workup.DISSOLUTIONThe residue was dissolved in methanol (20 mL)
5. 5
   여과filtered
6. 6
   농축concentrated
7. 7
   기타purified by column chromatography

실험 절차

To a solution of tetrahydro-4H-pyran-4-one (Aldrich) (7.22 g, 72.11 mmol) in cyclohexane (70 mL) were added pyrrolidine (6.26 mL, 7.57 mmol) and p-toluenesulfonic acid monohydrate (13.72 mg, 0.07 mmol). The reaction mixture was refluxed for 3 hours with a Dean-Stark trap, cooled and concentrated. The residue was dissolved in methanol (20 mL) and then sulfur (2.31 g, 72.11 mmol) was added followed by a solution of cyanamide (3.03 g, 72.11 mmol) in methanol (5 mL) at 0° C. The reaction mixture was stirred at room temperature overnight, filtered, concentrated and purified by column chromatography using an Analogix® Intelliflash280™ (SiO2, 0-5% methanol in dichloromethane) to afford the title compound. MS (ESI+) m/z 157 (M+H)+.

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