The solvent effects on the condensation reaction between tetraformylcavitand 2 and ethylene-1,2-diamine 3 are reported. Earlier, it was found that the trifluoroacetic acid-catalyzed condensation of 2 and 2 equiv of 3 in CHCl(3) provides in 82% yield an octahedral nanocage 1 composed of 6 cavitands that are linked together by 12 -CH=N-CH(2)CH(2)-N=CH- linker groups (Liu, X.; Liu, Y.; Li, G.; Warmuth, R. Angew. Chem., Int. Ed. 2006, 45, 901). In tetrahydrofuran, the same reactants yield a tetrameric nanocage 4 (35% yield), which resembles a distorted tetrahedron built up from four cavitands that occupy the apexes. Each cavitand is doubly linked to one other cavitand and singly linked to the other two cavitands via -CH=N-CH(2)CH(2)N=CH- connectors. In CH(2)Cl(2), the reaction between 8 2 and 16 3 yields a square antiprismatic nanocage 5 (65% yield), in which each cavitand occupies one of the eight corners and is connected to four neighboring cavitands via -CH=N-CH(2)CH(2)-N=CH- linkers. Nanocage 5 is also the main product in CH(2)ClCH(2)Cl (26% yield) and CHCl(2)CHCl(2) (33% yield). Reduction of all imine bonds in 4 and 5 yields polyaminonanocontainers 7 and 8, respectively, which were isolated as trifluoroacetate salts. Contrary to the formation of larger capsules composed of four, six, or eight cavitands in the reaction between 2 and 3, the acid-catalyzed reaction of 2 with 2 equiv of H(2)N-X-NH(2) (X = (CH(2))(n)(=3,4,5), 1,3-C(6)H(4), 1,4-(CH(2))(2)C(6)H(4), or 1,3-(CH(2))(2)C(6)H(4)) quantitatively yields octaiminohemicarcerands 9-14, in which two cavitands are connected with four -CH=N-X-N=CH- linkers. The outcomes of these condensation reactions are rationalized with the different diamine structures and the relative orientation of cavitands in 1, 4, 5, and 9-14.

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： Aggregationbehavioroftheroomtemperatureionicliquid(IL)[C 4 mim][BF 4 ]inD 2 OandCDCl 3 was studiedbythenuclearmagneticresonance(NMR)technique.Resultsindicatedthatprotonchemicalshiftsforthecation oftheILshiftdownfieldasthemolarfractionofILincreases.Theseprotonchemicalshiftschangerapidlyatlower concentrationsandleveloffathigherconcentrationsinD 2 O.ChemicalshiftsforH2onthecationshiftupfield.H4,H5, methylandmethyleneprotonsnexttothenitrogenofthecationshiftdownfieldasthemolarfractionofILincreases whiletheNMRsignalsforeachprotonchangesinCDCl 3 .Thecriticalaggregationconcentration(CAC)andthe aggregationnumberweredeterminedbyapplyingmassactiontheorytotheconcentrationdependenceofthe 1 HNMR chemicalshifts.Theseresultsarediscussedbasedontheinteractionsbetweenthecationandtheanionandthose betweentheILandthesolvents.

Depending on the shutter sequence used to initiate CdTe deposition, either (100) or (111) CdTe layers can be reproducibly grown on (100) ZnSe/GaAs substrates. Using a hexagonal surface model for (111) CdTe we propose a mechanism for the crystalline orientation selectivity. We use time‐resolved Kerr rotation to monitor the electron spin dynamics in these films. While the spin lifetime is found to depend on material quality, only (100) films show a clear temperature dependence, a peculiar feature we believe to arise from different residual strains in the layers with the two different orientations. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)