Strain relaxation, small ring molecules

Strain of small ring molecules cannot be fully understood in terms of the deviation of the bond angles from the ideal ones of the hybrid orbitals. The mechaitism of the relaxation of the strain has been proposed. Here, we briefly review a relaxation by the a—kj interactions between the geminal a bonds in the rings and % relaxation by the Ji—kj interaction between the endocyclic n bond with the vicinal a bonds on the ring atoms. A more detailed review is made by Naruse and Inagaki elsewhere in this volume. 

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