Interpreting the infrared spectrum of 1-methoxypropane

Doc Brown's Chemistry Advanced Level Pre-University Chemistry Revision Study Notes for UK IB KS5 A/AS GCE advanced A level organic chemistry students US K12 grade 11 grade 12 organic chemistry courses involving molecular spectroscopy analysing infrared spectra of 1-methoxypropane

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Spectra obtained from a liquid film of 1-methoxypropane. The right-hand part of the of the infrared spectrum of 1-methoxypropane, wavenumbers ~1500 to 400 cm^-1 is considered the fingerprint region for the identification of 1-methoxypropane and most organic compounds. It is due to a unique set of complex overlapping vibrations of the atoms of the molecule of 1-methoxypropane.

Interpretation of the infrared spectrum of 1-methoxypropane

The most prominent infrared absorption lines of 1-methoxypropane

A group of C-O stretching absorptions, from the ether linkage (C-O-C) are found around wavenumbers 1150 to 1060 cm^-1.

You get C-H bending/deformation vibration absorption bands at wavenumbers 1470 to 1365 cm^-1.

The C-H stretching vibration absorption bands are found in the 2800 to 3000 cm^-1  wavenumber region.

The absence of other specific functional group bands will show that a particular functional group is absent from the 1-methoxypropane molecular structure.