Observations: 9-Anthraldehyde: green/yellow fine powder, no clumps Benzyltriphen

Question

Observations: 9-Anthraldehyde: green/yellow fine powder, no clumps

Benzyltriphenylphosphonium chloride: white, shiny, very clumpy

DMF & NaOH – clear liquids

When DMF was added to 9-Anthraldehyde and Benzyltriphenylphosphonium chloride mix, the solution was dark green. When NaOH was added, the solution became very cloudy and as time went on, the solution turned a yellow/brown color. When 1:1 of 1-propanol/distilled water added, the solution thickened and turned into a jellylike consistency. Also, gold flakes formed in the “jelly”.

DISCUSSION QUESTION, THE END PRODUCT IS COLORED, WHY?

Explanation / Answer

For the given wittig reaction procedure,

Adding solvent DMF to a mixture of 9-anthraldehyde and benzyltriphenylphosphonium chloride gives the betaine formation. Adding NaOH gives the alkene product yellow in color.

Adding 1:1 mixture of 1-PrOH:water the solution thickened and turned into a jelly like due to the formation of alkene as solid, insoluble in the iPrOH-water mixture.

The end product formed is highly conjugated in nature and that's why it is colored.

Related Questions

Navigate

• Browse (All)
• Browse O
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.