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To explain 1 HNMR results where two different inclusion orientation isomer complexes of cucurbit [8]urils (Q[8], host)a nd protonated 3,4,7,8-tetramethyl-1,10-phenanthroline( guest) were observed.T he STO-3Ga nd B3LYP/3-21G * calculations were performedo nt he inclusion complexes of cucurbit[8]urils (Q[8], host) and protonated or free 3,4,7,8-tetramethyl-1,10-phenanthroline (guests). The results of ab initio and DFT energy calculations reveal that the " anti-"o rientation was a preponderant alternative structure in 1:2 complexes of Q[8] and the guest, and the inclusion complexes were stabilized by protonation of the guest. The pH influence was investigated which further confirmed these calculation results by electronic absorption spectroscopy.

The bioderived polycarbonate (ISB-PC) was synthesized via transesteri cation and polycondensation of isosorbide (ISB) and diphenyl carbonate (DPC), using lithium acetoacetone as catalyst. The resulting ISB-PC exhibited high glass transition temperatures similaring to bisphenol A polycarbonate (BPA-PC), and were thermally stable up to 350 ℃. The incorporation of isosorbitol into the polymer chain imparted an improved mechanical property of ISB-PC, such as a higher bending and tensile modulus and higher elongation at break. The ISB-PC can be readily cast into transparent lms with a tensile strength of 73.3 MPa and a tensile modulu of 534 MPa. The ISB-PC displayed a highly UV transmittance and possessed a blue uorescence under the UV irradiation. At the same time, ISB-PC also has strong anti-yellowing ability.

The nature of the supramolecular host-guest complex involving 4pyrrolidinopyridine (BuPC4) and cucurbit [6]uril (Q[6]) has been investigated by NMR and UV spectroscopy, MALDI-TOF mass spectrometry, X-ray crystallography and isothermal titration calorimetry (ITC). The results revealed that the alkyl chain of the guest BuPC4 is located inside the cavity of the Q[6] host, whereas the other section of the BuPC4 guest remains outside of the portal.

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