Synthese,Kristallstruktur und Konformation vontrans-[2.2](1,2)Ferrocenophan und seinen 1-Hydroxyderivaten

Starting from1-(dimethylaminomethyl)-2-iodo-ferrocene (3) 2.2](1,2)ferrocenophane (2) was prepared in an 8-step synthesis with 17% overall yield. Both from the oxoderivative12 and the ferrocenophane2 puretrans-isomers (12b and2b, resp.) were obtained; the former (12b) was reduced to a separable mixture ofexo andendo 1-hydroxy-ferrocenophanes13a andb, resp. (～ 3:7), the configurations of which were assigned by the LIS-method. X-ray crystal structure analysis of2b revealed a centrosymmetrical chair conformation. From¹H- and¹³C-NMR spectra both for2b and for the hydroxyderivatives13 a rigidexo-exo chair conformation was deduced.