Q8(c)(ii). Structure of C₄H₅NO₂
An unknown organic compound with molecular formula C₄H₅NO₂ displays a band at 2250 cm⁻¹ and a strong band at 1740 cm⁻¹ in the IR spectrum. The compound shows only two signals in 3 : 2 ratio in the ¹H NMR spectrum. Find out the structure of the compound. Justify your answer.
Answer in brief
Methyl cyanoacetate, N≡C–CH₂–CO₂CH₃.
Part of VKC Basic
Read the key points and the full model answer with VKC Basic
VKC Basic (₹999 for 6 months) opens every solved answer, the notes, the handbook and the daily answer archive. Every Mains test series includes it.
The full model answer
As written for the answer booklet: the diagram carries the working, the lines stay short. Read here only; it is not offered as a download.
Coversmethyl cyanoacetateIR spectroscopynitrile stretchester carbonylstructure elucidation
All parts of Question 8
- 8(a)(i) Coupling constants of the lettered protons5 marks
- 8(a)(ii) Chemical shifts of Hᵃ and Hᵇ5 marks
- 8(a)(iii) Number of ¹H NMR signals5 marks
- 8(b)(i) Structure of the halogenated ester10 marks
- 8(b)(ii) C₆H₁₂ alkenes with peaks at m/z 42 and 565 marks
- 8(c)(i) Characteristic fragment ions10 marks
- 8(c)(ii) Structure of C₄H₅NO₂10 marks