Ring strain and the negative pole. V. The interaction of a strained system with non-directly bonded charge

Abstract

The electrostatic interaction of small rings with charge is used to explain the reactivity of several compounds involved in solvolyses, and in particular exo and endo fused rings of 7-syn and 7-anti substituted norbornanes. Provided that the interaction between the ring and the leaving group is accounted for, the calculated results are in good accord with experiment. In particular, the effect of a cyclopropyl or vinyl group forced into the ?crown? conformation on an adamantyl carbonium ion is accountable. The ease of protonation of a strained system is discussed, and the edge protonation of bicyclobutane is calculated to be faster than bridgehead protonation. Tetrahedrane is predicted to be protonated by any trace of water. Boranes are compared with protonated hydrocarbons and the structures of some simple boranes are rationalized. The existence of a new stable isomer of B₄H₁₀ is predicted.