Synthesis of p-terf-butylcalix[4]arene semitubes and their binding studies with C_(60)

摘要

The synthesis of β-tert-butylcalix[4]arene semitubes in one step reaction with fairly good yields is described. The structures of these compounds were confirmed by ~1H NMR, ~(13)CNMR and mass spectrometry. The complexation ability of these compounds with C_(60) was investigated and found that they are able to form 1:1 complexes. The stability constants of these complexes were determined and found to be 15,203 and 525 dm~3 mol~(-1) for the semitubes 3a, 3b, 3c respectively. The binding energies of each of C_(60), the semitubes and the complexes are calculated using PM6 (Semiempirical quantum chemical) and DFT (Density Functional Theory) methods and found in the order m>p >o. On the other hand, the calculated binding energies using DFT method showed that the stabilities of both centered and side complexes are in the order p >m >o.