Anomalous Energy Effects Associated with the Presence of Aza Nitrogens and NitroSubstituents in Some Strained Systems

摘要

We have used an ab initio SCF molecular orbital approach in conjunction with theisodesmic reaction procedure to investigate anomalous energy effects in strained aza systems and some of their nitro derivatives. The introduction of nitrogens into strained molecular frameworks is found to confer added degrees of stability. IN general this increases with the number opf nitrogens in a series of similar molecules. Further stabilization results from N-nitro substitution and the mononitration of secondary carbons; however the polynitration of systems containing highly strained tertiary carbons has a marked destabilizing effect. Keywords: Ab initio self-consistent-field molecular orbital calculations; Isodesmic reactions; Strained aza systems; Nitro derivatives; Strain energy. (js)