Baeyer’s strain

Woker attempts to apply this strain theory to ring compounds, and considers that the five carbon atom ring produces less strongly odoured substances than any other and points out that, according to Baeyer s strain theory, the five carbon ring has the least internal tension. It is very doubtful if this contention is correct, since the penta-methylenes do not seem to be less strongly odoured than other polymethylene ring compounds. ... 

It will be seen that whereas iodine leads to 1 2 tetra- and di-basie esters, methylene, ethylene, etc., iodides yield respectively 1 3, 1 4, etc., esters. The yields in these ring syntheses, as in most others, vary in agreement with Baeyer s Strain Theory. ... 

Mohr, E. Die Baeyersche Spannungstheorie und die Struktur des Diamanten. [Baeyer s strain theory and the structure of diamond.] Chemisches Zentralblatt 2, 1065 (1915). 

Structure A typical alicyclic hydrocarbon. It exists in two modifications called the boat and the chair, as shown. This is due to slight distortion of the bond angles in accordance with the modified version of Baeyer s strain theory. Cyclohexane has been studied extensively on a theoretical basis in a branch of advanced chemistry called conformational analysis. See conformation. 

Structure X in Figure 300 shows interpenetrating tetrahedra with carbon centers and a single bond between these carbons. Van t Hoff correctly postulated that there is free rotation about such single bonds. Structures XIa, Xlb, XII, and XIII rationalize cis and Irons isomerism (e.g., the difference between maleic acid and fumaric acid). Structure XIV explains the widespread occurrence of six-membered rings in chemistry and aspects of Baeyer s strain theory. ... 

Baeyer s strain theory applies to rings with atoms in a single plane. It is not necessary for the atoms to be in a single plane, and all sorts of odd rings can be (and are) formed in which this restriction does not hold. 

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