207563-98-2Relevant academic research and scientific papers
The coordination and rearrangement of some organic chalcogenides on a rhodium-rhodium bond; The reactions with dialkylsulfanes and alkanethiols
Devery, Michael P.,Dickson, Ron S.,Fallon, Gary D.,Skelton, Brian W.,White, Allan H.
, p. 195 - 206 (2007/10/03)
When solutions of [Cp2Rh2(μ-CO)(μ-η2:η 2-CF3C2CF3)] (I) in petroleum ether or chlorinated hydrocarbons were treated with the dialkylsulfanes SRR′(R=R′=Me, Et, Pr, Bz; RR′=MeEt), the addition products [Cp2Rh2(CO)(SRR′)(μ-η1:η 1-CF3C2CF3)] (III, a-e) were formed reversibly. The complexes (III) have been characterized spectroscopically in solutions containing excess ligand. Removal of excess ligand and solvent regenerated (I). When left in solution, a number of the dialkylsulfane complexes underwent interesting transformations. The complex (IIIa, R=R′=Me) converted to [Cp2Rh2{μ-η1:η2-C(CF 3)C(CF3)H}(μ2-SEt)] (IVa, R=Et); this involves a β-proton transfer accompanied by a Stevens rearrangement to convert {S(CH2-)CH3} to (SCH2CH3)-. The structure of (IVa) was determined by X-ray crystallography. Two rearrangement products were formed when (IIIb, R=R′=Et) was left in solution. One was characterized from spectroscopic data as [Cp2Rh2{μ-η1:η2-C(CF 3)C(CF3)H}(μ2-SCHMeEt)] (IVb), which is formed by a Stevens rearrangement after transfer of a β-proton. The other was identified as (IVa, R=Et), which is formed after proton abstraction from a γ-carbon followed by elimination of ethene. A number of μ-thiolato complexes (IVa-h, R=Me, Et, Pr, CHMeEt, Pri, Bu, But and Ph) were formed directly by treatment of (I) with the appropriate alkanethiol RSH. In some instances (R=CHMeEt, Pri, and But), a second product of formula [Cp2Rh2(μ-CO){μ-η2:η 1-CH(CF3)C(CF3)SCR1R 2R3)] (VI, a-c) was formed. The molecular structure of (VIb, R1=H, R2=R3=Me) was determined by single crystal X-ray diffraction analysis.
