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Synthesis and Studies of Symmetrical DitelluraCalix[6]phyrin(1.1.1.1.1.1)s
Md Ashif Ali1, Mangalampalli Ravikanth1
1Indian Institute of Technology Bombay, Powai, Mumbai 400076, India.
Abstract:
Rare examples of ditellura calix[6]phyrin(1.1.1.1.1.1)s containing two telluratripyrrin units connected via two sp3 carbons were synthesized by condensing 16-telluratripyrrane with a cyclic ketone in CH2Cl2 under acid-catalyzed conditions. The X-ray structure obtained for meso-cyclohexyl-substituted calix[6]phyrin revealed that the macrocycle resembles a roof-like shape with two telluratripyrrin units that are perpendicular to each other, whereas the DFT-optimized structure of meso-cyclopentyl-substituted calix[6]phyrin showed a bird-like structure with two telluratripyrrin units that are almost in the same plane.
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