CHM 25500 Lecture Notes - Lecture 9: Ring Strain, Cyclohexane Conformation, Cyclopropane
14 Jul 2015
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Document Summary
Angle strain: the increase in potential energy of a molecule due to bond angles deviating from the ideal values . All carbons are in the same plane. Bond angles are very far from ideal tetrahedral bond angles (109. 5 degrees), resulting in lots of angle strain. C-h bonds are eclipsed resulting in torsional strain as well. 88 degree bond angles still cause angle strain. 6. 5 kcal/mol more energy than chair conformation. Bonds in boat conformation can rotate slightly to form twist boat conformation, which is 1 kcal/mol lower in energy than boat conformation. Chair conformation is the most stable conformation of cyclohexane. Equatorial - in plane of ring parallel to c-c bonds. One of each of these types is attached to each carbon. Each of these types can face up or down. If you number the carbons in the ring, every other carbon is oriented up, and the ones in between are oriented down.
