(Pentamethylcyclopentadienyl)rhodium(III) Dichloride Dimer

Typical Procedure:
N-Benzoyl-4-methylbenzenesulfonamide (27.5 mg, 0.1 mmol), [RhCl₂Cp*]₂ (1.2 mg, 0.002 mmol) and Cu(OAc)₂·H₂O (40.0 mg, 0.2 mmol) are loaded in a dry vial which is subjected to evacuation/flushing with dry argon three times. A solution of 2,6-dimethylphenyl isocyanide (19.6 mg, 0.15 mmol) in anhydrous dichloroethane (0.8 mL) is syringed into the mixture that is then stirred at 130 °C for 20 h or until the starting material has been consumed as determined by TLC. Upon cooling to room temperature, all volatiles are evaporated and the residue is purified by preparative TLC (ethyl acetate : hexane = 1 : 2) to give the corresponding 3-(imino)isoindolinone derivative (Y. 70%, E/Z = 3 : 1). Z and E isomers are further separated by preparative TLC (methylene chloride : hexane = 10 : 1).