Friedel-Crafts Alkylations (Exp.II)

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Today IR Next time (see our website!) Partition
coefficient and partition calculations Separation
s of mixtures
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Infrared (IR) spectroscopy
http//www.chem.ucla.edu/webspectra/index.html

• IR region 4000 - 400 cm-1 (cm-1 unit is the
  wave number scale and is given by 1/wavelength in
  cm) E h n

• IR spectroscopy deals with the interactions
  between a molecule and radiation from the IR
  region of the electromagnetic spectrum
• IR radiation causes the excitation of the
  natural vibrations of covalent bonds within that
  molecule and includes stretching and bending
  modes (C 334 molecular modeling experiments!)

• Excitation of the natural vibrations of a bond
  leads to absorption of light of typical
  frequencies. This is recorded as a minimum on the
  IR spectrum.
• The frequencies are typical for the atoms and
  bond types involved and allow us to determine
  functional groups.

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Fingerprint region
butyl acetate
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http//www.chem.ucla.edu/webspectra/index.html
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http//www.chem.ucla.edu/webspectra/index.html
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Aromatics
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http//www.chem.ucla.edu/webspectra/index.html
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http//www.chem.ucla.edu/webspectra/index.html
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Alcohols
OH non-hydrogen bonded
Gas phase!
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Phenol
OH hydrogen bonded
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(No Transcript)
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Ketones
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Carboxylic Acids
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C6H12O2
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Next time Partition coefficient and partition
calculations Separations of mixtures (Print out
from our Website and bring to class)