Esquema de sección

  • Learning Goals:  Understand why different protons in a molecule have different chemical shifts, including the role of shielding by electrons, deshielding caused by nearby electronegative elements, and the role of ring currents for protons bound to carbons that are part of pi bonding systems.   Understand what leads to NMR Splitting.  Know that "J" represents the splitting between peaks and is measured in Hz (not ppm).  Know intensity patterns for equal J splitting by 2, 3, 4, 5, or 6 nuclei.   Also be able to use chemical shift charts and tables of functional group effects upon chemical shifts to predict chemical shifts for a given structure.

    Reading: Soderberg sections on coupling. 

    Resource: The two-page document "NMR Chemical Shift Prediction for Chem 111" is a resource you should print out.  You will need it to understand pencast 11B.

    Notes: Review the pencasts* below.  (*-Audio from old pencasts does not work.  Ignore the warning about needing to update to latest Adobe Reader - see note in first topic).