Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Rhodium(II) acetate is the chemical compound with the formula Rh2(AcO)4, where AcO is the acetate ion (CH3CO2 ). This emerald green powder is a catalyst for cyclopropanation of alkenes. It is also used as catalyst for insertion into C-H and X-H bonds (X = N/S/O) and for ylide formation for organic syntheses. Rhodium(II) acetate is usually prepared by the heating hydrated rhodium(III) chloride in acetic acid (CH3COOH): Rhodium(II) acetate dimer undergoes ligand exchange, the replacement of the acetate group by other carboxylates and related groups.