Studies on Stereoselective Electrophiic Cyanation The enantioselective, electrophilic cyanation of the enolates of 2‐substituted 1‐tetralones 3 is described. Enantiomerically pure 2‐cyanato‐1,1′‐binaphthyl derivatives 2, 6a and b are used as cyanating agents. The influence of solvent, temperature, additives and the method of enolate formation are investigated. Best results are obtained with 48% ee in the case of compound 2 and 60% ee in the case of compound 6b if the enolate is prepared from the corresponding silyl enol ether 7 and Toluene is used as solvent.

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The thermal stability of purified endohedral Li@C 60 has been studied. There are two endohedral compounds produced from Li + irradiated C 60 that have slightly different stabilities. The endohedral species decay at elevated temperatures on a time scale of a few hours when in solution and exposed to light and air. The dry, purified material has a higher thermal stability and can be sublimed in vacuum to produce thin films of pure endohedral fullerenes.

Synthesis, Structure, and Photophysical Properties of Polyarylated Imidazoles and Oxazoles 23 tetraphenylimidazoles 1,2 and 11 triphenyloxazoles 4,5 with amino, nitro, methoxy, hydroxy, or halogeno substituents chiefly in the para position were prepared. The absorption and fluorescence emission properties were investigated in ethanolic solution. The effects of the substituents in 1,2 on the spectral shifts show that the arrangement of the phenyl rings in 1 position is not coplanar in relation to the heterocycle whereas the phenyl rings in 2 position are more coplanar. The spectral changes of compound 2a in solvents of various polarity (dielectric constants 2,02–47,24) are almost negligible. The Stokes shift is moderately increased. A remarkable increase in the fluorescence quantum yield is observed by chlorine substitution in phenyl ring 2.

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