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? 

Read More

How strong was your coffee this morning?

How strong was your coffee this morning?

Who doesn’t want to start the day with a warm cup of coffee? Coffee has a stimulating effect on humans because of its caffeine content and for that reason it has become one of the most popular drinks in the world. Some clinical studies actually suggest that small amounts of caffeine everyday might be beneficial for adults. In this blog I am going to highlight an experiment done in collaboration with the Swager group at MIT using an organometallic complex to quantify the caffeine content in regular coffee without sample preparation!

Read More

'Hop' off the Diagonal: COSY spectrum of α-humulene

'Hop' off the Diagonal: COSY spectrum of α-humulene

NMR spectroscopy is by far the most useful characterization technique in organic chemistry, especially if you have to elucidate the structure or configuration of your products. Arguably, 2D experiments such as COSY, HSQC, and HMBC have simplified this task tremendously. In this post I wanted to highlight the COSY of α-humulene. 

Read More

What to expect: Chemical Shifts & Coupling Constants in Low-field NMR Spectroscopy

One of the questions that we always get at tradeshows and conferences is how our instrument compares to high-field data. There are significant inherent differences between low-field and high-field instruments, but the most important from a chemistry point of view are sensitivity (S/N) and resonance dispersion (signal separation).

Read More

A watched pot never boils… how to monitor reactions the easy way!

A watched pot never boils… how to monitor reactions the easy way!

When monitoring reaction progress for determination of reaction kinetic parameters, NMR spectroscopy has increasingly become the method of choice. The ease in which one can calculate the concentration changes of a substrate being consumed or a product being formed over time, directly from peak integration are the reason behind this.

Read More