The Dangers of Making Too Many Assumptions. Electronegativity, Acidity, and Chemical Shift

The Dangers of Making Too Many Assumptions. Electronegativity, Acidity, and Chemical Shift

Last month (which you can see here), we learned about how an acidic proton behaves in a 1H NMR experiment, particularly when it’s surrounded by D2O. For example, when an H+ leaves CH3COOH to join an accommodating D2O molecule, the resulting acetate (H3CCOO–) segment is reasonably comfortable bearing that negative charge. This phenomenon is the reason the solution is “acidic” in the first place. But why is acetate so capable of dealing with this negative electronic charge?

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Boron NMR Spectroscopy

Boron NMR Spectroscopy

For my first blog I have decided to talk a little bit about boron because it’s a fascinating element that imparts remarkable properties to its compounds. And believe me, there are hundred of different compounds with very different properties containing boron centers. We find boron in compounds like boronic acids (A), boronic esters (B), and MIDA boronates (C), all of which are very popular in Suzuki coupling reactions to make new C–C bonds.  Another popular family of compounds containing boron are the BODIPY dyes (D). These derivatives, composed of a dipyrromethene ligand supporting a BF2 unit, are used as stable functional dyes in several fields, but their application as biomolecular labels is the most investigated by far.

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