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What is number of 1H NMR signals for toluene?
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Michael Woram
What is number of 1H NMR signals for toluene?
In general, the aromatic region of any $\ce{^1H-NMR}$ spectrum would display a complex coupling pattern even if for mono substituted nucleus such as toluene. However, your $\ce{^1H-NMR}$ spectrum is taken by using a low field NMR instruments such as 60 MHz, you'd not able to get one with good resolution to show these patterns (other factors involve in having broad multiplets instead of resolved peaks are low quality calibration, RF instability, etc.). The following spectrum is taken using a high resolution NMR instrument. The $\delta~7.70-7.70$ region was expanded to show the coupling pattern of 5 aromatic hydrogens. In a low-field instrument, those peaks would overlap to give you a broad multiplet. Read this article to learn about basic principles of coupling patterns.
In general, the aromatic region of any $\ce{^1H-NMR}$ spectrum would display a complex coupling pattern even if for mono substituted nucleus such as toluene. However, your $\ce{^1H-NMR}$ spectrum is taken by using a low field NMR instruments such as 60 MHz, you'd not able to get one with good resolution to show these patterns (other factors involve in having broad multiplets instead of resolved peaks are low quality calibration, RF instability, etc.). The following spectrum is taken using a high resolution NMR instrument. The $\delta~7.70-7.70$ region was expanded to show the coupling pattern of 5 aromatic hydrogens. In a low-field instrument, those peaks would overlap to give you a broad multiplet. Read this article to learn about basic principles of coupling patterns.
The phrase, "number of signals" has a broad meaning, and it is based on the person who asking the question in this case. For example, there are signals for three magnetically different hydrogens in this spectrum. But, your teacher may consider a doublet as two signals.More
Question should ask for the number of non equivalent protons rather than for a variable depending on experimentals. Or both the asker and whom is asked should be open for circumstancesMore
Thanks for answering my query, but then what should I answer for a question when asked me about number of signal should I consider it as a high resolution ?More
In general, the aromatic region of any $\ce{^1H-NMR}$ spectrum would display a complex coupling pattern even if for mono substituted nucleus such as toluene. However, your $\ce{^1H-NMR}$ spectrum is taken by using a low field NMR instruments such as 60 MHz, you'd not able to get one with good resolution to show these patterns (other factors involve in having broad multiplets instead of resolved peaks are low quality calibration, RF instability, etc.). The following spectrum is taken using a high resolution NMR instrument. The $\delta~7.70-7.70$ region was expanded to show the coupling pattern of 5 aromatic hydrogens. In a low-field instrument, those peaks would overlap to give you a broad multiplet. Read this article to learn about basic principles of coupling patterns.
In general, the aromatic region of any $\ce{^1H-NMR}$ spectrum would display a complex coupling pattern even if for mono substituted nucleus such as toluene. However, your $\ce{^1H-NMR}$ spectrum is taken by using a low field NMR instruments such as 60 MHz, you'd not able to get one with good resolution to show these patterns (other factors involve in having broad multiplets instead of resolved peaks are low quality calibration, RF instability, etc.). The following spectrum is taken using a high resolution NMR instrument. The $\delta~7.70-7.70$ region was expanded to show the coupling pattern of 5 aromatic hydrogens. In a low-field instrument, those peaks would overlap to give you a broad multiplet. Read this article to learn about basic principles of coupling patterns.
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