हिंदी
कर्नाटक बोर्ड पी.यू.सी.पीयूसी विज्ञान 2nd PUC Class 12

Complete the synthesis by giving missing starting material, reagent or product. CA6HA5CHO....................+......→Δdil⋅NaOH...CHA3CHA2CHO............ - Chemistry

Advertisements
Advertisements

प्रश्न

Complete the synthesis by giving missing starting material, reagent or product.

\[\begin{array}{cc}
\ce{C6H5CHO}\phantom{............}\\
\phantom{........}\ce{+\phantom{......}\ce{->[dil.NaOH][\Delta]}}\phantom{...}\\
\ce{CH3CH2CHO}\phantom{............}
\end{array}\]

रासायनिक समीकरण/संरचनाएँ
Advertisements

उत्तर

\[\begin{array}{cc}
\phantom{......................................................}\ce{CH3}\\
\phantom{...................................................}|\\
\ce{\underset{Benzaldehyde}{C6H5CHO} + \underset{Propanal}{CH3CH2CHO} ->[dil.NaOH][Claisen-Schimdt reaction]\underset{2-Methyl-3-phenyl-prop-2-enal}{C6H5\overset{3}{C}H = \overset{2}{C} - \overset{1}{C}HO}}
\end{array}\]

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 8: Aldehydes, Ketones and Carboxylic Acids - Exercises [पृष्ठ २५७]

APPEARS IN

एनसीईआरटी Chemistry Part 1 and 2 [English] Class 12
अध्याय 8 Aldehydes, Ketones and Carboxylic Acids
Exercises | Q 8.17 (vii) | पृष्ठ २५७

संबंधित प्रश्न

Write the products formed when CH3CHO reacts with the following reagents: CH3CHO in the presence of dilute NaOH


Which of the following compounds would undergo aldol condensation, which the Cannizzaro reaction and which neither? Write the structures of the expected products of aldol condensation and Cannizzaro reaction.

  1. Methanal
  2. 2-Methylpentanal
  3. Benzaldehyde
  4. Benzophenone
  5. Cyclohexanone
  6. 1-Phenylpropanone
  7. Phenylacetaldehyde
  8. Butan-1-ol
  9. 2, 2-Dimethylbutanal

How will you convert ethanal into the following compound?

Butane-1, 3-diol


How will you convert ethanal into the following compound?

But-2-enal


Write structural formulas and names of four possible aldol condensation products from propanal and butanal. In each case, indicate which aldehyde acts as nucleophile and which as electrophile.


How will you bring about the following conversion in not more than two steps?

Ethanol to 3-Hydroxybutanal


Describe the following:

Cross aldol condensation


 Why is alpha (α) hydrogen of carbonyl compounds acidic in nature?


Which product is formed when the compound  is treated with concentrated aqueous \[\ce{KOH}\] solution?


Which of the following compounds do not undergo aldol condensation?

(i) \[\ce{CH3 - CHO}\]

(ii)  

(iii)  \[\begin{array}{cc}
\phantom{}\ce{O}\\
\phantom{}||\\
\ce{CH3 - C - CH3}
\end{array}\]

(iv) \[\begin{array}{cc}
\phantom{}\ce{CH3}\\
|\phantom{...}\\
\ce{CH3 - C - CHO}\phantom{..}\\
|\phantom{...}\\
\phantom{}\ce{CH3}\\
\end{array}\]


Compound ‘A’ was prepared by oxidation of compound ‘B’ with alkaline \[\ce{KMnO4}\]. Compound ‘A’ on reduction with lithium aluminium hydride gets converted back to compound ‘B’. When compound ‘A’ is heated with compound B in the presence of \[\ce{H2SO4}\] it produces fruity smell of compound C to which family the compounds ‘A’, ‘B’ and ‘C’ belong to?


Why are carboxylic acids more acidic than alcohols or phenols although all of them have hydrogen atom attached to a oxygen atom \[\ce{(-O-H)}\]?


Assertion: The α-hydrogen atom in carbonyl compounds is less acidic.

Reason: The anion formed after the loss of α-hydrogen atom is resonance stabilised.


Give reasons to support the answer:

Presence of Alpha hydrogen in aldehydes and ketones is essential for aldol condensation.


Which of the following gives aldol con~ensation reaction?


Identify A and B from the following reaction:

\[\begin{array}{cc}
\ce{CH3}\phantom{.................}\\
|\phantom{....................}\\
\phantom{}\ce{2CH3 - C = O ->[Ba(OH)2] A ->[Δ] B + H2O}
\end{array}\]


Predict the reagent for carrying out the following transformations:

Ethanal to 3-hydroxy butanal


\[\ce{CH3-CH2-CHO ->[dil][alkali] Product}\]

The product in the above reaction is:


Why is the α-hydrogens of aldehydes and ketones are acidic in nature?


Write a note on the aldol condensation reaction of acetaldehyde.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×