2D NMR Experiments - HETCOR

2D NMR Experiments -  HETCOR

2D NMR experiments can provide an abundance of information for the structural elucidation of chemical compounds. An older example of a 2D experiment is the heteronuclear correlation (HETCOR) sequence. In this experiment, two different nuclei (usually 13C and1H) are correlated through single bond spin-spin coupling, revealing which proton and carbon groups are bonded to each other.

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Two solvents, two different spectra - Aromatic Solvent Induced Shifts

In my opinion, one of the most helpful papers[1]in the field of NMR spectroscopy in Organic Chemistry consists of ‘just’ two tables. In these, the chemical shifts (1Hand 13C) of as many as forty-two common impurities in twelve different deuterated solvents are listed. This is gold! Why? We know, that the signals of one and the same compound can show a rather high discrepancy in its chemical shifts in different solvents. But did you also know, that there is a concept called Aromatic Solvent Induced Shifts (ASIS), which benefits from this fact? 

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Heteronuclear Spin-Spin Coupling on the NMReady-60PRO

Heteronuclear Spin-Spin Coupling on the NMReady-60PRO

Spin-spin coupling is an important facet of 1H NMR spectroscopy, as crucial details about the structure of a molecule are revealed based on the pattern of multiplets observed. In general, the signal for a group of equivalent protons will be split into a multiplet based on the n+1 rule, where nis the number of equivalent protons that are adjacent to the protons. For example, the signal of the CH2 protons in an ethyl group will be observed as a quartet (adjacent to three equivalent protons; 3+ 1) while the signal for the CH3protons in the same ethyl group will be a triplet (adjacent to two equivalent protons; 2+ 1).

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Getting COSY with the TOCSY Experiment

Getting COSY with the TOCSY Experiment

2D NMR experiments can provide a wealth of information to aid in the structural elucidation of chemical compounds. Of the many 2D NMR experiments available, the homonuclear correlation spectroscopy (COSY) sequence is one of the most popular and is used to identify which spin systems are directly coupled to each other. As an example, the 1H-1H COSY spectrum of 1-propanol recorded on the NMReady-60 is shown below in Figure 1.

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