The structure of compound L is to be proposed and the assignment for the peaks in IR spectrum is to be done. Concept introduction: IR spectroscopy is used to determine the presence of functional groups in the compounds. NMR spectroscopy is used to determine the presence of equivalent protons in the structure of the compound. In the IR spectra, benzene shows absorption at 3030 cm -1 for the C − H stretching. Monosubstituted benzene gives peaks between 690 and 770 cm -1 . Para di-substituted benzene gives a strong peak between 800 and 860 cm -1 . Aromatic rings show absorption at 3030 cm -1 due to C − H stretching and between 1600-1400 cm -1 due to C=C stretching vibrations. Alkyl groups show absorption between 2950 and 2850 cm -1 due to C − H stretching.

Question

Want to see the full answer?

Answer 1

Question

Chapter 14, Problem 34P

Interpretation Introduction

Interpretation:

The structure of compound L is to be proposed and the assignment for the peaks in IR spectrum is to be done.

Concept introduction:

IR spectroscopy is used to determine the presence of functional groups in the compounds.

NMR spectroscopy is used to determine the presence of equivalent protons in the structure of the compound.

In the IR spectra, benzene shows absorption at 3030 cm-1 for the C−H stretching. Monosubstituted benzene gives peaks between 690 and 770 cm-1.

Para di-substituted benzene gives a strong peak between 800 and 860 cm-1.

Aromatic rings show absorption at 3030 cm-1 due to C−H stretching and between 1600-1400 cm-1 due to C=C stretching vibrations.

Alkyl groups show absorption between 2950 and 2850 cm-1 due to C−H stretching.

Expert Solution & Answer

Want to see the full answer?

Check out a sample textbook solution

See solution

Students have asked these similar questions

A compound (L) with the molecular formula C9H10 reacts with bromine and gives an IR absorption spectrum that includes the following absorption peaks: 3035 cm ¹(m), 3020 cm ¹(m), 2925 cm ¹(m), 2853 cm ¹(w), 1640 cm ¹1(m), 990 cm ¹(s), 915 cm ¹(s), 740 cm ¹(s), 695 cm ¹(s). The ¹H NMR spectrum of L consists of: Doublet 3.1 ppm (2H) Multiplet 5.1 ppm Multiplet 7.1 (5H) ppm Multiplet 4.8 ppm Multiplet 5.8 ppm The UV spectrum shows a maximum at 255 nm. Propose a structure for compound L. Edit Drawing h

The IR spectra of nonane (C,H20) and 1-hexanol (C,H13OH) are shown below. Assign each spectrum to the correct compound and identify the frequencies and the functional groups used to support your assignment. λ (μη) 6 7 8 9 10 11 12 1314 15 2.5 100 3 5 20 4 90 80 70 60 50 40 30 20 10 4000 3600 3200 2800 2400 2000 1800 1600 1400 1200 1000 800 600 400 Frequency (cm¬') A (µm) 2.5 100 8 9 10 11 12 13 14 15 3 4 5 7 20 90 80 70 60 50 40 30 20 10 4000 3600 3200 2800 2400 2000 1800 1600 1400 1200 1000 800 600 400 Frequency (cm¬!) (%) Transmission (%) Transmission

The 13C NMR spectrum of fluoroethanoic acid shows a multiplet centred at δ = 79. When the same spectrum is recorded using proton decoupling, the multiplet collapses to a doublet with a splitting of 160 Hz. Another multiplet, but with much smaller splittings, is also seen centred at δ =179; this multiplet collapses to a doublet when decoupling is used. Explain these observations.