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Configuration and conformational mobility of [12] annulene from NMR studies at various temperatures

✍ Scribed by Jean F.M. Oth; J.-M. Gilles; G. Schröder

Publisher
Elsevier Science
Year
1970
Tongue
French
Weight
315 KB
Volume
11
Category
Article
ISSN
0040-4039

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✦ Synopsis

As shown in the preceding note 2) , a 75% pure [ lZ]annulene can be synthesized by UV irradiation of syn-tricyclo[ 8.2.0.0 2'9]d d o eta-3.5.7.1i-tetraene at -ilO"C. We have investigated the temperature dependent NMR spectrum of this compound in order i) to establish its configuration in terms of the number and the sequence of cis and trans double bonds, and ii) to study the reversible dynamic process occurring in this molecule.

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