‘Face‐to‐Face’‐Benzo‐anellierte homologe Hypostrophene. Synthesen, Röntgenstrukturanalysen und PE‐Spektren

‘Face-to-Face’ Benzo-anellated Homologous Hypostrophenes. Syntheses, X-Ray-Structure Analyses and PE Spectra ‘Face-to-face’ Benzo-anellated homologous hypostrophenes (series M), of interest as substrates for [6 + 6]-photocycloaddition reactions, have been synthesized. From X-ray structural analyses of 13b and 13c shortest CC distances of 2.80(2.76)/2.71 A and interorbital angles (ω) of 129° (128°)/130° between the benzene rings have been determined. The PE spectra are discussed in the context of transannular π,π interactions.