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N-(2 0 -R-Phenyl)-9,10-dihydro-9,10-ethanoanthracene-11,12-dicarboximides with R ¼ Me (1), OMe (2), OEt (3) and H (4) were investigated. The crystal and molecular structures of 1-3, determined by single crystal methods, show different conformations of the N-(2 0 -R-phenyl) group. Anti conformations and weak intermolecular CH/p contacts were found in 2 and 3, while anti and syn conformations coexist in 1 with CH/p contacts being absent. Solid-state 13 C CP/MAS spectra confirm the X-ray molecular structural data. Two crystallographically independent molecules in the unit cell of 2 correspond to two isotropic chemical shifts for C atoms in the CP/MAS spectrum. The different molecular dynamics of both molecules in the crystal lattice of 2 indicated by the thermal factors and intermolecular CH/p contacts were clearly visible in different crosspolarisation profiles. The NMR data of 4 suggest that the phenyl ring bonded to the nitrogen is nearly coplanar to the ethanocarboximide ring. Full assignment of liquid state 1 H and 13 C NMR spectra of 1-4 was possible by application of high field NMR spectroscopy. Some incorrect assignments of 13 C chemical shifts in the literature were revised. The different ratios of [syn]: [anti] in solutions of chloroform and DMSO are explained in terms of different intermolecular CH/p interactions.y Electronic supplementary information (ESI) available: figures of the conformations in compound 1 and the molecular packing and intermolecular CH/p interactions in compounds 2 and 3. See

Fluorescence of the inclusion complexes with different compositions tbrmed by naphthalene-h s. naphthalene-d~. 2,7-dimethylnaphth,,tene tDM N). and 2-benzyln,~phthalene ~ BN) with [~-cyclodextrin (~-CD) in wa~er was studied. Two types of fluorescence are observed, monomer (MF) and excimer (EFt fluorescence The excimer fluorescence of the 2 : 2 complex emitted by aggregated light-dispersing crystals forming a precipitate, whereas ix the MF is obseceed in the transparent solution When naphthalene and ]]-CD are present in equimolar concentrations, EF predominates for the resulting complexes. A proposed structure of the inclusion complexes was derived from MNDO/PM3 semiempirical quantum-chemical calculations. The EF is caused by ~he structure of fl~e complex, in which both uaphtha)ene molecules are separated by a distance of 4.'7 A they lie in parallel orientation to each other, wilereb 5 one ring is displaced from the other by one-fourth of the length of the naphthalene ring. The complexes of 2.7-DMN and 2-benzyh~aphthalene with ~-CD do not exhibit EF. For the 2 : 2 complex of 2,7-DMN with II-CD, this i,, due to the fact that the aromatic fragments arc removed to~ {ar fronl one another 2-Bcnzyinaphdmlenc is unable to form an incluszon complex with i~-CD, in who~e structure the alomatic fragmen~.s hlside ~he cavity could be :Jrranged in parallel planes; instead, il Ik~rms a I : 2 complex with I~-.CD.Key words: ~-cyclodex{rin, naphthalene, naphthalene derivatives, inclusion complexes, structure of inclusion complexes, fluorescence, e\cimer fluorescence, scmiempirical quamumchemical calculations, MNDO/PM3 mettmd.Excimer fluorescence (EF) is due to the tbrmation of an excited direct of the AA* type having a relatively long lifetime (hundreds of nanoseconds) and subsequent light emission upon transformation of this dimer into two molecules A. which do not interact in the ground state. In solutions, the dimeric structure favorable for the origination of EF arises upon diffusion of molecules A. Obviously, the probability of this process increases with increase in the concentration of the molecules: for arenes, EF can be obse~ed at concentrations of about 1 M.! The efficiency of excimer generation is characterized by the ratio of El = intensity to the intensity of monomer fluorescence (MF) at their maxima K = lexc/Irnow We used this coefficient for quantitative estimates.On passing to molecular-organized systems of the host--guest type, the formation of the corresponding dimeric structure and generation of EF is no longer determined by diffusion processes" instead, they are determined by the probability of formation of inclusion complexes containing two A molecules whose mutual orientation can facilitate the formation ofexcimers, For naphthalene, its derivatives, and analogs, the most suitable host molecules are cyclodextrins (CD) z and, in particular, ~3-cyclodextrin (13-CD). Its molecule, shaped like a basket, consists of seven c~-D-glucopyranose umts linked by (I--4) glucoside bonds. 3 The internal wall in the cavity of ...

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