Q46.Isobutyraldehyde on reaction with formaldehyde and K2 CO3 gives compound ' A '. Compound ' A' reacts with KCN and yields compound ' B ', which on hydrolysis gives a stable compound ' C '. The compound ' C ' is (1) (2) (3) (4)
What This Question Tests
This multi-step synthesis problem involves the crossed Cannizzaro reaction (hydroxymethylation), followed by nucleophilic substitution with KCN, and finally hydrolysis of a nitrile to a carboxylic acid.
Concepts Tested
📚 NCERT Sections This Tests
8.6 — Predict The Products Formed When Cyclohexanecarbaldehyde Reacts With
Chemistry Class 12 · Chapter 8
8.6 Predict the products formed when cyclohexanecarbaldehyde reacts with following reagents. (i) PhMgBr and then H3O + (ii) Tollens’ reagent (iii) Semicarbazide and weak acid (iv) Excess ethanol and acid (v) Zinc amalgam and dilute hydrochloric acid 8.7 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. (i) Methanal (ii) 2-Methylpentanal (iii) Benzaldehyde (iv) Benzophenone (v) Cyclohexanone (vi) 1-Phenylpropanone (vii) Phenylacetaldehyde (viii) Butan-1-ol (ix) 2,2-Dimethylbutanal 8.8 How will you convert ethanal into the following compounds? (i) Butane-1,3-diol (ii) But-2-enal (iii) But-2-enoic acid 8.9 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. 8.10 An organic compound with the molecular formula C9H10O forms 2,4-DNP derivative, reduces Tollens’ reagent and undergoes Cannizzaro reaction. On vigorous oxidation, it gives 1,2-benzenedicarboxylic acid. Identify the compound. 8.11 An organic compound (A) (molecular formula C8H16O2) was hydrolysed with dilute sulphuric acid to give a carboxylic acid (B) and an alcohol (C). Oxidation of (C) with chromic acid produced (B). (C) on dehydration gives but-1-ene. Write equations for the reactions involved. 8.12 Arrange the following compounds in increasing order of their property as indicated: (i) Acetaldehyde, Acetone, Di-tert-butyl ketone, Methyl tert-butyl ketone (reactivity towards HCN) (ii) CH3CH2CH(Br)COOH, CH3CH(Br)CH2COOH, (CH3)2CHCOOH, CH3CH2CH2COOH (acid strength) (iii) Benzoic acid, 4-Nitrobenzoic acid, 3,4-Dinitrobenzoic acid, 4-Methoxybenzoic acid (acid strength) 8.13 Give simple chemical tests to distinguish between the following pairs of compounds. (i) Propanal and Propanone (ii) Acetophenone and Benzophenone (iii) Phenol and Benzoic acid (iv) Benzoic acid and Ethyl benzoate (v) Pentan-2-one and Pentan-3-one (vi) Benzaldehyde and Acetophenone (vii) Ethanal and Propanal 8.14 How will you prepare the following compounds from benzene? You may use any inorganic reagent and any organic reagent having not more than one carbon atom (i) Methyl benzoate (ii) m-Nitrobenzoic acid (iii) p-Nitrobenzoic acid (iv) Phenylacetic acid (v) p-Nitrobenzaldehyde. 8.15 How will you bring about the following conversions in not more than two steps? (i) Propanone to Propene (ii) Benzoic acid to Benzaldehyde (iii) Ethanol to 3-Hydroxybutanal (iv) Benzene to m-Nitroacetophenone (v) Benzaldehyde to Benzophenone (vi) Bromobenzene to 1-Phenylethanol (vii) Benzaldehyde to 3-Phenylpropan-1-ol (viii) Benazaldehyde to a-Hydroxyphenylacetic acid (ix) Benzoic acid to m- Nitrobenzyl alcohol 8.16 Describe the following: (i) Acetylation (ii) Cannizzaro reaction (iii) Cross aldol condensation (iv) Decarboxylation Chemistry 256 Reprint 2025-26
9.9 — Give The Structures Of A, B And C In The Following Reactions:
Chemistry Class 12 · Chapter 9
9.9 Give the structures of A, B and C in the following reactions: B NaOH Br 2 C (i) CH 3 CH 2 I NaCN A Partial OHhydrolysis CuCN H 2 O/H NH 3 (ii) C 6 H 5 N 2 Cl A B C 4 B HNO 2 C (iii) CH 3 CH 2 Br KCN A LiAlH 0 C 2 2 O/H HCl B H C (iv) C6 H 5 NO 2 Fe/HCl A NaNO273 K 3 A NaOBr B NaNO 2 /HCl C (v) CH 3 COOH NH 2 B C 6 H 5 OH C (vi) C6 H 5 NO 2 Fe/HCl A HNO273K 279 Amines Reprint 2025-26
8.4 — Write The Iupac Names Of The Following Ketones And Aldehydes. Wherever
Chemistry Class 12 · Chapter 8
8.4 Write the IUPAC names of the following ketones and aldehydes. Wherever possible, give also common names. (i) CH3CO(CH2)4CH3 (ii) CH3CH2CHBrCH2CH(CH3)CHO (iii) CH3(CH2)5CHO (iv) Ph-CH=CH-CHO CHO (v) (vi) PhCOPh
📋 Question Details
- Chapter
- Aldehydes Ketones Carboxylic Acids
- Topic
- Cannizzaro Reaction and Nitrile Hydrolysis
- Year
- 2022
- Shift
- 28 Jun Shift 2
- Q Number
- Q46
- Type
- MCQ
- NCERT Ref
- Class 12 Chemistry Ch 12: Aldehydes, Ketones and Carboxylic Acids
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