A metallostannylene complex, Cp*(iPr2MeP)(H)2Fe-SnDMP (Cp* = η5-C5Me5; DMP = 2,6-dimesitylphenyl), exhibits diverse reactivity that demonstrates the ability of the Fe-Sn linkage to adopt differing degrees of multiple bonding and varying geometries (e.g. linear vs. bent). One-electron oxidation of this complex affords the 17e radical cation {Cp*(iPr2MeP)Fe=SnDMP}+, with accompanying loss of dihydrogen. EPR and DFT studies identify this complex as an iron-based radical with significant positive charge accumulation on the tin atom. Surprisingly, one-electron reduction of the cation does not afford the expected neutral complex Cp*(iPr2MeP)Fe[SnDMP], but instead results in the activation of a phosphine ligand C-H bond to produce Cp*HFe(κ2-(P,Sn)=Sn(DMP)CH2CHMePMeiPr). The C-H activated product is also obtained upon thermolysis of the parent metallostannylene, Cp*(iPr2MeP)(H)2Fe-SnDMP, in a process that is kinetically first order in this complex. DFT studies suggest that the C-H bond activation likely occurs across the Fe---Sn linkage of an intermediate- Cp*(iPr2MeP)Fe[SnDMP]- via a concerted process, rather than a through a radical-based mechanism.

Variations in Fe-Sn bonding interactions in a metallostannylene system: Multiple bonding and C-H bond activation

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.