Preparation, Structure, and Anion Sensing Properties of 1,n-Diaza[n]ferrocenophanes
datasetposted on 2005-08-19, 00:00 authored by Francisco Otón, Alberto Tarraga, Arturo Espinosa, Maria D. Velasco, Delia Bautista, Pedro Molina
The synthesis of structurally new types of azaferrocenophanes is reported in this note: 4, which comprises a 1,2-fused azaheterocycle to a 1,3-diazaferrocenophane framework; 1,3-diazaferrocenophanes 5 and 7, which can be considered as a 1,1‘-ferrocenylene N,N‘-guanidine or urea, respectively; and 1,3,6,8-tetrazaferrocenophanes 9 and 10, bearing two ureido moieties in the ansa-bridge. These compounds were prepared directly from 1,1‘-bis(isocyanato)ferrocene 1 and thoroughly characterized by spectroscopic means. Tetrazaferrocenophanes 9 and 10 show spectral and electrochemical anion-sensing action: they display a selective downfield shift of the urea protons and a cathodic shift of the ferrocene/ferrocinium redox couple with dihydrogenphosphate and fluoride anions. The crystal structure of compound 4 has been determined by single-crystal X-ray methods.
ferrocenespectroscopicfluoride anionsdisplayazaheterocyclecrystal structuremethodredoxdownfield shiftcompound 4typePropertiessynthesisurea protonsbiAniondihydrogenphosphatecouplePreparationframeworkDiazaguanidinecathodic shifttetrazaazaferrocenophaneTetraza10 showferrocenophaneelectrochemicaldiazaferrocenyleneureido moieties