What could be the compound in this spectra with peaks at 154 and 154+2?

In summary, the conversation is about analyzing a set of unknown compounds using spectroscopy techniques. The IR band at ~1700 suggests the presence of a carbonyl oxygen, while the band at ~1200 and ~2900 indicate a saturated ester. In the mass spec, the molecular ion peak at 154 and the 3:1 peak ratio indicate the presence of chlorine. The peak at 118 suggests the loss of HCl. In the 1H NMR, there is a multiplet peak with 7 peaks and an integration of 1, indicating the presence of two equivalent methyl groups. The 13C NMR shows different environments for CH3, CH2, CH, and quaternary C.
  • #1
Respect-rometry
3
0
Hi guys

As part of my degree I've got to analyses a set of spectras unknown compounds. I've managed to do them all so far, but seem to be struggling on this one particular set.

Here's the spectra that I have to analyse: http://imgur.com/a/oVNYe

So far I think it might be an ester with a Alkyl chloride in it.

Any help is greatly appreciated!
 
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  • #2
Please elaborate on what you see and how you get to the conclusions.
 
  • #3
Borek said:
Please elaborate on what you see and how you get to the conclusions.
Sure.

Strong IR band at ~1700 indicates presence of carbonyl oxygen. In a Spectroscopy book I've got from the library, the band at ~1200 is supposedly indicative of a saturated ester. The band at ~2900 also suggests an ester

In the mass spec. The molecular ion peak is 154, with an M+2 showing a +2 isotope is present. The 3:1 peak ratio shows its Chlorine due to the 75:25 relative abundances of 35Cl& 37Cl. The peak at 118 is indicative of loss of HCl

There is a peak at 43 which I thought what a C-H group with two methyl groups and a C=O group attached. This is because there is a multiplet peak in the 1H NMR with 7 peaks and an integration of 1. So that would come from the H atom coupling to the two equivalent methyl groups.

The 13C NMR shows which environments are CH3, CH2, CH and quaternary C environments.

This is what I've got so far, so any help would be great
 
  • #4
Respect-rometry said:
The peak at 118 is indicative of loss of HCl

MS is not something I feel confident about, but if you have peaks at 154 and 154+2, and HCl is lost, shouldn't you have a similar pair at 118 and 118+2?
 
  • #5
Borek said:
MS is not something I feel confident about, but if you have peaks at 154 and 154+2, and HCl is lost, shouldn't you have a similar pair at 118 and 118+2?
No there shouldn't be a significant 118+2 peak, because Cl is being lost and so the 37Cl isotope won't be present anymore. Hence there is no 3:1 peak ratio in the mass spectra at 118 & 120
 

Related to What could be the compound in this spectra with peaks at 154 and 154+2?

What is organic spectroscopy?

Organic spectroscopy is a branch of chemistry that uses various techniques to analyze the chemical structure and composition of organic compounds. It involves the use of light, radiation, and other forms of energy to study the interactions between molecules and their environment.

What are the different types of organic spectroscopy?

Some commonly used types of organic spectroscopy include infrared spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry, and ultraviolet-visible (UV-Vis) spectroscopy. Each technique has its own strengths and limitations, and they are often used in combination to obtain a more comprehensive understanding of a compound.

How is organic spectroscopy used in research?

Organic spectroscopy is an important tool in chemical research, as it allows scientists to identify and characterize the structure of new compounds. It is also used to study the reactivity and behavior of molecules, and can provide valuable information for drug discovery, environmental analysis, and other areas of study.

What are the advantages of using organic spectroscopy?

Organic spectroscopy allows for non-destructive analysis of compounds, meaning that the sample is not altered or destroyed during the testing process. It is also a highly sensitive technique, capable of detecting even small amounts of a substance. Additionally, it is relatively quick and cost-effective compared to other methods of analysis.

What are the limitations of organic spectroscopy?

While organic spectroscopy is a powerful tool, it does have some limitations. For example, certain compounds may not produce a strong signal or may be difficult to analyze with certain techniques. Additionally, the interpretation of spectroscopic data requires a high level of expertise and may be subject to human error.

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