Semicarbazones Carbonyl compounds Mix 1 mL of the semi carbazide hydrochloride with 40 mg of the unknown. Add 1mL of methanol to make the solution clear. Add 15 drops of pyridine and warm on a water bath for 5 min. Cool to room temperature, put in ice, and scratch to induce crystallization. Collect the product by suction filtration and wash with cold water. Recrystallize from methanol, ethanol, or ethanol-water mixture and let it dry until next time. 2,4 Dinitrophenylhydrazones Mix 2.5 mL of 2,4-dinitrophenylhydrazine in phosphoric acid and 25 mg of the unknown. Warm in a water bath for 5 min and let crystallization proceed. Collect the product by suction filtration and wash the crystals with cold water. Recrystallize from ethanol and let it dry until next time. NHÁNH, Re N-NH- -NO₂ + R✗ R' O₂N NO₂ R' O₂N Re NH₂ H₂N N-NH2 R'

Semicarbazones Carbonyl compounds Mix 1 mL of the semi carbazide hydrochloride with 40 mg of the unknown. Add 1mL of methanol to make the solution clear. Add 15 drops of pyridine and warm on a water bath for 5 min. Cool to room temperature, put in ice, and scratch to induce crystallization. Collect the product by suction filtration and wash with cold water. Recrystallize from methanol, ethanol, or ethanol-water mixture and let it dry until next time. 2,4 Dinitrophenylhydrazones Mix 2.5 mL of 2,4-dinitrophenylhydrazine in phosphoric acid and 25 mg of the unknown. Warm in a water bath for 5 min and let crystallization proceed. Collect the product by suction filtration and wash the crystals with cold water. Recrystallize from ethanol and let it dry until next time. NHÁNH, Re N-NH- -NO₂ + R✗ R' O₂N NO₂ R' O₂N Re NH₂ H₂N N-NH2 R'

Macroscale and Microscale Organic Experiments

7th Edition

ISBN:9781305577190

Author:Kenneth L. Williamson, Katherine M. Masters

Publisher:Kenneth L. Williamson, Katherine M. Masters

Chapter7: Extraction

Section: Chapter Questions

Problem 1Q

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