Konkave Farbstoffe mit Azobenzol‐Einheiten als Chromophore, Photoschaltelemente und hohlraumbildende Bausteine

Concave Dyes with Azobenzene Units as Chromophores, Photoswitchable and Cavity‐Forming Elements Five monomacrocyclic ( 12a–e ) and three types of threefold azobenzene‐bridged oligomacrocyclic compounds ( 15, 17, 28, 31 ) have been synthesized. Due to the cavity‐forming chromophores at the periphery of these molecules they represent concave dyes. The watersoluble monocycles 12b–e were photoisomerized and investigated before and after E/Z isomerization with regard to their host properties for small neutral organic guest compounds. The bicyclic azobenzene derivative 31 with triphenylethane spacers exhibits in/out isomerism. The in/out isomer 31c was separated by HPLC from 31a and b , which are in equilibrium at room temperature. The tris(2‐aminoethyl)amine‐capped Schiff bases 15 and 17 form complexes with Cu(CH 3 CN) 4 BF 4 .