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Synthesis and specific fluoride binding properties of expanded dithiacalixphyrins
Emandi Ganapathi1, Tamal Chatterjee, Mangalampalli Ravikanth
1Department of Chemistry, Indian Institute of Technology, Powai, Mumbai 400076, India. ravikanth@chem.iitb.ac.in.
Abstract:
Expanded dithiacalixphyrins with the N(2)S(2) core containing two sp(3) and three sp(2) meso-carbons have been prepared by condensation of one equivalent of butene-2,3-diyl-bisthiophene-2,5-diyl-bis(p-methoxyphenylmethanol) with one equivalent of 5,5'-dialkyldipyrromethane under mild acid catalyzed conditions in decent yields. The expanded dithiacalixphyrins were characterized by HR-MS, 1D and 2D NMR techniques and the structure of one of the expanded dithiacalixphyrin macrocycles was solved by X-ray crystallography. The crystal structure analysis indicated that the macrocycle is highly distorted and attains a boat shaped structure. The expanded thiacalixphyrins showed a specific sensing ability for F(-) ions over other anions as judged from absorption, NMR and mass spectral studies.
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