Synthesis, characterization, and fluorescence and cytotoxicity studies of a tetrarhenium molecular rectangle

An one-pot reaction of Re-2(CO)(10) with 4,4'-bipyridyl (4,4'-bpy) in refluxed 1-pentanol afforded the molecular rectangle, [(CO)(3)Re(mu-OC5H11)(2)Re(CO)(3)](2){mu-(4,4'-bpy)}(2) (I), in almost quantitative yield. The molecular rectangle, I, has been characterized spectroscopically and by X-ray crystal structure determination. Compound I exhibits fluorescence and is cytotoxic against cancer cell lines. (c) 2007 Elsevier B.V. All rights reserved.