Q.54. - Organic Chemistry

Question

Question: Which of the diethylbenzene isomers (ortho, meta, or para) corresponds to each set of ${}^{\mathbf{13}}\mathit{C}$ NMR spectral data?

[A] ${}^{\mathbf{13}}\mathit{C}$NMR signals: 16, 29, 125, 127.5, 128.4, and 144 ppm

[B] ${}^{\mathbf{13}}\mathit{C}$ NMR signals: 15, 26, 126, 128, and 142 ppm

[C] ${}^{\mathbf{13}}\mathit{C}$ NMR signals: 16, 29, 128, and 141 ppm

Step-by-Step Solution

Answer

Answer

 

The ortho isomer corresponds to spectral data [B], meta isomer corresponds to spectral data [A], and para isomer corresponds to spectral data [C].

Step 1: C 13   N M R

The carbon atoms in a particular molecule can be spotted with the NMR spectroscopy technique termed ${}^{\mathbf{13}}\mathit{C}$ NMR spectroscopy. Several organic compounds can be characterized with the help of ${}^{\mathbf{13}}\mathit{C}$ NMR.

Step 2: Spectral analysis

The analysis of various parameters like frequency, energy,etc can be done using spectral analysis. Several practical problems in various fields like engineering and science can also be solved with the help of spectral analysis.

Step 3: Number of C 13 NMR signals exhibited by each compound

The ortho isomer of diethylbenzene can be given as:

Ortho isomer of diethylbenzene

 

The given compound has five types of carbon atoms. Hence it will have five signals, and this compound corresponds to spectral data [B].

The meta isomer of diethylbenzene can be given as:

Meta isomer of diethylbenzene

 

The given compound has six types of carbon atoms. Hence, it will have six signals, and this compound corresponds to spectral data [A].

The para isomer of diethylbenzene can be given as:

Para isomer of diethylbenzene

 

The given compound has four types of carbon atoms. Hence, it provides four signals, and the compound corresponds to spectral data [C].