Evan L. Allred

Fast atom bombardment mass spectrometry of isomeric pyrazolinium salts under matrixless conditions

Abstract Fast atom bombardment mass spectrometry of solid matrixless samples of pyrazolinium salts give spectra with molecular ions that are suitable for structural analysis and differentiation between isomeric structures.

A norbornenyl derivative with through-space ketone π-interaction

The title compound, endo,exo-12-oxotetracyclo[6.2.1.1(3,6).0(2, 7)]dodeca-9-en-anti-11-yl p-bromobenzoate, C(19)H(17)BrO(3), consists of norbornene with an anti-p-bromobenzoate substituent at the methano bridge and an exo-fused norbornanone unit bonded to the ethano bridge. The spatially proximate ketone and alkene interact through space and the ketone C atom is substantially pyramidalized. Through-space ketone pi-interaction is probably responsible for the low solvolysis rate of the anti-11-chloride derivative.

Structural investigations of a tetracyclic endo-norborenyl derivative

The X-ray crystal structure of endo,exo-tetracyclo-[6.2.1.1 3,6 .0 2,7 ]dodec-9-en-anti-11-yl p-bromobenzoate, C 19 H 19 BrO 2 (1), was determined at 148 K. The molecule consists of norbornene with an anti-p-bromobenzoate substituent at the methano bridge and an exo-norbornyl unit endo-fused to the ethano bridge. Structural comparisons are made with another derivative and steric interactions examined

Structural comparisons of a perpendicular diene with known derivatives

The X-ray crystal structure determination of endo,exo-12-methylenetetracyclo[6.2.1.1 3,6 .0 2,7 ]dodec9-en-anti-11-yl p-bromobenzoate, C 20 H 19 BrO 2 (1), is reported. The molecule consists of norbornene with an anti-p-bromobenzoate substituent at the methano bridge and an exo-methylenenorbornyl unit endo-fused to the ethano bridge. The ring C atom of the exocyclic double bond is pyramidalized significantly. Steric interactions are examined and some structural comparisons are made with other derivatives

Thermolysis of azo-compounds: a reactivity factor of 1017

Incorporation of cyclopropyl and cyclobutyl groups in the 2,3-diazabicyclo[2,2,2]oct-2-ene system has been found to increase the thermoloysis rates by factors of ca. 1017 and 105, respectively.