## Abstract The enthalpies of formation of 2,7‐dimethyl‐4,5‐benzotropone (I), 2,7 ‐ pentamethylene‐ 4,5 ‐ benzotropone (III) and 2,7 ‐ dodeca‐methylene‐ 4,5‐benzotropone (II) have been determined by combustion calorimetric methods. The loss of 36 kcal/moles in delocalisation energy for III relative
Untersuchungen in der Benztropylium-Reihe. V. Die Dipolmomente des 2,3-Benztropons, des 4,5-Benztropons und 2,7-disubstituierter 4,5-Benztropons
✍ Scribed by T. Gäumann; R. W. Schmid; E. Heilbronner
- Publisher
- John Wiley and Sons
- Year
- 1956
- Tongue
- German
- Weight
- 493 KB
- Volume
- 39
- Category
- Article
- ISSN
- 0018-019X
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✦ Synopsis
Abstract
The dipole moments of 2,3‐benztropone (11), 4,5‐benztropone (III) and of 2,7 dialkyl‐substituted 4,5‐benztropones have been determined. The difference in dipole moment between II and III can be attributed to differences in geometry, rather than to varying amounts of polar character. Attention is drawn to the exceptional dipole contribution of alkyl gronps in 2,7 ‐dimethyl‐4,5‐benztropone and 2,7 ‐do deca‐ methglene‐4,5‐beuztropone (VIII). Dipole as well as molecular refraction data confirm conclusions drawn in previous publications about the relative geometries of VIII and of 2,7‐pentamethylene‐4,5‐benztropone.
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## Abstract The polarographic half wave potentials of 2,3‐benztropone, 4,5‐benztropone, 2,7‐dimethyl‐4,5‐benztropone and 2,7‐polymethylene‐ 4,5‐benztropones have been determined. The half wave potentials of the latter series of compounds support the conclusions drawn in previous publications concer
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