A ferrocenyl-bridged intramolecularly coordinated bis(diorganostannylene): Synthesis, molecular structure and reactivity of [4-t-Bu-2,6-{P(O)(O-i-Pr)2C6H2Sn}C5H4]2Fe

The intramolecularly coordinated heteroleptic stannylene [4-t-Bu-2,6-{P(O)(O-i-Pr)2}2C6H2]SnCl serves as synthon for the synthesis of the ferrocenyl-bridged bis(diorganostannylene) [4-t-Bu-2,6-{P(O)(O-i-Pr)2}2C6H2SnC5H4]2Fe (1) which in turn reacts with W(CO)6 and Cr(CO)4(C7H8) to provide the corresponding transition metal complexes [4-t-Bu-2,6-{P(O)(O-i-Pr)2}2C6H2Sn{W(CO)5}C5H4]2Fe (2) and [4-t-Bu-2,6-{P(O)(O-i-Pr)2}2C6H2SnC5H4]2Fe · Cr(CO)4 (3), respectively. Reaction of compound 1 with sulphur and atmospheric moisture gave, under partial tin–carbon and oxygen–carbon bond cleavage, a tetranuclear organotin-oxothio cluster 5. All compounds were characterized by 1H, 13C, 31P, and 119Sn NMR, and IR spectroscopy, as well as by single-crystal X-ray diffraction analysis. Compounds 1 and 3 were also investigated by Mössbauer spectroscopy. Cyclovoltametric studies reveal the influence of the organostannyl moieties on the redox-behaviour of compounds 1–3 in comparison with unsubstituted ferrocene.

Graphical abstractThe first example of a ferrocenyl-bridged bis(diorganostannylene) (1) holds potential as both bis-monodentate and bidentate ligand in transition metal chemistry and reacts with appropriate metal carbonyls to give the complexes 2 and 3, respectively. Compound 1 reacts in an unprecedented manner with sulphur and atmospheric moisture to give the organotin-oxothio cluster 5.Figure optionsDownload full-size imageDownload as PowerPoint slide