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While for small molecules standard 1D proton measurements are mostly sufficient to do a full structural assignment, larger molecules often require the information from additional homo- and hetero- nuclear correlation experiments for an unambiguous assignment. As for such molecules often only a limited amount of substance is available it is important that the NMR-spectrometer provides …

Structure verification of Brucine by advanced homo and heteronuclear NMR. Read More »

SPHOS (2-Dicyclohexylphosphino-2′,6′-dimethoxybiphenyl) is a widely used air-stable phosphine ligand employed together with e.g palladium in a range of different catalytic reactions. Figure 1 shows the 1H NMR spectrum of a 800 mM SPHOS sample in CDCl3 measured in a single scan taking 15 seconds to acquire.   Figure 1: 1H NMR spectrum of a 800 …

Characterizing SPHOS by 1H, 13C and 31P NMR. This phosphine ligand is widely employed together with e.g palladium in a range of different catalytic reactions. Read More »

 1H Spectra   5-Bromo-1,2,3-trifluorobenzene (BrC6H2F3) is a structurally simple molecule commonly used as a building block in a variety of synthetic organic reactions. As this molecule contains 1H, 19F, and 13C (in natural abundance), it is a beautiful example to demonstrate the unique advantage offered by the Spinsolve of accessing all three nuclei simultaneously without requiring …

How simultaneous decoupling of 1H and 19F can help to simplify crowded 13C spectra – A Multi-nuclei case study on 5-Bromo-1,2,3-trifluorobenzene without the need of user intervention Read More »

Paliperidone is the essential metabolite of risperidone, an atypical antipsychotic employed for the treatments of schizophrenia or bipolar disorders. Its chemical structure consists of a benzisoxazole moiety and it is less lipophilic than risperidone. Being an example of atypical antipsychotics, it acts more as a serotonin-receptor blocker than a dopamine-receptor one. The interested reader is …

Paliperidone – Verify the structure of your products by combining 1D and 2D NMR experiments Read More »

In a previous application note we described the advantages and prerequisites for performing qNMR with an internal standard. However, this method is not easy to implement on samples taken directly from the production line.  In this case, the main complication comes from the fact that the type of sample preparation required to add an internal …

qNMR on samples from the production plant – Quantify multiple analytes without sample preparation in the presence of protonated solvents with a single measurement. Read More »

Ethylene Propylene Diene Monomer (EPDM) is a synthetic terpolymer rubber  prepared from ethylene, propylene, and non-conjugated diene monomers that are incorporated in the polymer chain to enable crosslinking via vulcanization. After polymerization and purification, free diene monomer can remain in the copolymer. Detection and quantification of this monomer is important as it impacts the vulcanization …

Detection and quantification of free double bond in Ethylene Propylene Diene Monomer (EPDM) Read More »

The Spinsolve Ultra benchtop NMR spectrometer can be easily used to look at some of the main components in milk, like water, fat, and lactose.  Milk contains around 87% of water, therefore the water signal dominates the spectrum and overlaps with the signal of some of the other components in the sample. Running a PRESAT …

Determination of lactose, fat and water content in milk Read More »

Honey is a well-known natural food source, made by bees using nectar from flowers. Typically honey is classified by color and flavor depending on the type of flower from which the nectar was harvested from. Pure honey is a complex supersaturated solution containing 80% sugars and unique combination of chemical compounds such as phenolic, flavonoids, …

Identification and quantification of methylglyoxal in Manuka honey Read More »