Flash-photolytic experiments showed that the photocyclisation of 1,2-di(2-naphthyl)ethylene, (Ia), results in the formation of two isomeric 4a,4b-dihydro-phenanthrenes derived from two of the possible three conformers of (Ia), and differing in thermal stability by a factor of 1010.
闪光光解实验表明,1,2-二(2-萘基)乙烯(I a)的光环化导致形成两个异构体4a,4b-二氢菲,它们衍生自( I a),并且热稳定性相差10 10。
sym-1,2-Diarylethylenes from .alpha.-lithiated benzylic sulfones. Catalysis by elemental tellurium