Chlorobis(cyclooctene)rhodium dimer is an organorhodium compound with the formula Rh2Cl2(C8H14)4, where C8H14 is cis-cyclooctene. Sometimes abbreviated Rh2Cl2(coe)4, it is a red-brown, air-sensitive solid that is a precursor to many other organorhodium compounds and catalysts.
The complex is prepared by treating an alcohol solution of hydrated rhodium trichloride with cyclooctene at room temperature.Van der Ent, A.; Onderdelinden, A. L. "Chlorobis(cyclooctene)rhodium(I) and di-μ-chlorobis[bis(cryclooctene)iridium] (I) complexes" Inorganic Syntheses 1973, volume 14, pp. 92-5. The coe ligands are easily displaced by other more basic ligands, more so than the diene ligands in the related complex cyclooctadiene rhodium chloride dimer.
Catalyst for C-H activation C-H activation is often catalyzed by chlorobis(cyclooctene)rhodium dimer as demonstrated in the synthesis of a strained bicyclic enamine.
The synthesis of a mescaline analogue involves enantioselective annulation of an aryl imine via a C-H activation.
The total synthesis of lithospermic acid employs "guided C-H functionalization" late stage to a highly functionalized system. The directing group, a chiral nonracemic imine, is capable of performing an intramolecular alkylation, which allows for the rhodium-catalyzed conversion of imine to the dihydrobenzofuran.
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