Attached Proton Test, an 'APT' experiment for structural elucidation

Attached Proton Test, an 'APT' experiment for structural elucidation

A key step towards elucidating structures with NMR spectroscopy is the assignment of signals to specific groups within the molecule being analyzed. Two experiments, DEPT (Distortionless Enhancement by Polarization Transfer) and APT (Attached Proton Test), are typically used to aid this process with 13C NMR spectra.1 Both experiments are similar in that the number of attached protons (i.e. the multiplicity) is revealed by the phase of the 13C NMR signals. The key difference between the DEPT and APT experiment is that signals for quaternary carbons are observed in the APT experiment.

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To Decouple or Not to Decouple, That is the Question. Also….Acids.

To Decouple or Not to Decouple, That is the Question.  Also….Acids.

Acidity is something that you encounter on a daily basis, probably without even realizing it. The tangy taste of an orange (citric acid), that Vitamin C tablet you took this morning (ascorbic acid), those terrible jeans from the 80’s that you still wear (acid wash). My favourite acid is acetic acid.

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