Tuesday, 25 April 2017

The Wonders of Chemistry: HOW TO CALCULATE COUPLING CONSTANTS IN NMR

The Wonders of Chemistry: HOW TO CALCULATE COUPLING CONSTANTS IN NMR: The signals of protons, which have other magnetically inequivalent protons at geminal or vicinal positions are split because of spin-...

HOW TO CALCULATE COUPLING CONSTANTS IN NMR




The signals of protons, which have other magnetically inequivalent protons at geminal or vicinal positions are split because of spin-spin coupling between these neighboring protons. The splitting of the signal can be measured by calculating the coupling constant of the concerned signal. Coupling constant is a constant value, independent of the magnetic field strength and it mostly depends upon the extent of interaction between two proton systems. Denoted by “J”, the values of coupling constants are calculated in Hz.

Monday, 24 April 2017

The Wonders of Chemistry: HOW TO DRAW A COUPLING TREE IN NMR

The Wonders of Chemistry: HOW TO DRAW A COUPLING TREE IN NMR: Coupling tree is a pattern developed as a result of the splitting of signals in 1H-NMR due to spin-spin coupling. The tree tells us ...

HOW TO DRAW A COUPLING TREE IN NMR





Coupling tree is a pattern developed as a result of the splitting of signals in 1H-NMR due to spin-spin coupling. The tree tells us about the splitting pattern of the signal and also helps in calculation of the coupling constant.

Monday, 24 October 2016

The Wonders of Chemistry: Is Stereoselectivity a Problem? Try Enzymes

The Wonders of Chemistry: Is Stereoselectivity a Problem? Try Enzymes: Stereoselectivity is a major issue in synthetic organic chemistry. The use of chiral reagents and catalysts can solve the problem t...

Is Stereoselectivity a Problem? Try Enzymes




Stereoselectivity is a major issue in synthetic organic chemistry. The use of chiral reagents and catalysts can solve the problem to a greater extent. But there are problems associated with the use of these chemicals as they may be expensive, hard to get, and most of the time not friendly for the environment. Enzymes, the biological catalysts, have been used as chiral catalysts for carrying out stereoselective reactions, mainly because of their specific nature. Enzymes are proven to be environmentally benign.

Thursday, 6 October 2016

The Wonders of Chemistry: SIGNAL GENERATION IN NMR

The Wonders of Chemistry: SIGNAL GENERATION IN NMR: We know that a spin active nucleus behaves as a tiny magnet under the influence of a strong magnetic field. Such nuclei have an intri...

SIGNAL GENERATION IN NMR




We know that a spin active nucleus behaves as a tiny magnet under the influence of a strong magnetic field. Such nuclei have an intrinsic property of arranging themselves in all possible spin states in the presence of a magnetic field. The possible spin states can be calculated from the spin quantum number.

Thursday, 29 September 2016

The Wonders of Chemistry: PRINCIPLE OF NMR SPECTROSCOPY

The Wonders of Chemistry: PRINCIPLE OF NMR SPECTROSCOPY: Nuclear Magnetic Resonance (NMR) spectroscopy is a powerful technique employed for various analytical purposes, especially structur...

PRINCIPLE OF NMR SPECTROSCOPY




Nuclear Magnetic Resonance (NMR) spectroscopy is a powerful technique employed for various analytical purposes, especially structural characterization of organic compounds.