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Tuning of Heterocyclic Ring in Para-Benzi Heterosapphyrins
Vratta Grover1, Mangalampalli Ravikanth1
1Indian Institute of Technology, Powai, Mumbai, 400076, India.
Abstract:
Three examples of moderately aromatic p-benzi dithiasapphyrin and p-benzi tellurathiasapphyrins have been synthesized by condensing p-benzithiophene diol with 16-thia/telluratripyrrane under acid-catalyzed reaction conditions. The X-ray structural analysis showed that the thiophene ring in p-benzi dithiasapphyrin was inverted, whereas the tellurophene ring in p-benzi tellurathiasapphyrins was normal conformation with respect to the macrocyclic core. However, NMR studies revealed that the thiophene ring in protonated p-benzi dithiasapphyrin flips to normal, whereas the tellurophene ring in p-benzi tellurathiasapphyrins flips to inverted orientation.
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