Iodine → (S)-1-Ethyl-5-methylpiperazin-2-one

Beteiligte Stoffe

Reaktionsschritte

A mixture of chloro-1,5-cyclooctadiene iridium (I) dimer (34 mg, 51 μmol) and (S)-1-[(R)-2-di-(3,5-bis(trifluoromethyl)phenyl)phosphino)ferrocenyl]ethyldicyclohexylphosphine (44 mg, 51 μmol; Solvias AG, SL-J006-2) in a mixture of 1:2 toluene and methanol (100 mL; purged with nitrogen for 15 minutes) was sonicated under an atmosphere of nitrogen for 15 minutes. To the resultant mixture, iodine (0.39 g, 1.52 mmol) and 1-ethyl-5-methylpyrazin-2(1H)-one (7.0 g, 50.66 mmol) was added. The resultant mixture was heated in an oil bath at 50° C. under an atmosphere of hydrogen gas at 800 psi for 48 hours. The product mixture was filtered through a pad of Celite. The filtrate was concentrated under vacuum. The residue was treated with chloroform saturated with ammonia gas (100 mL). The resultant suspension was filtered through a pad of Celite, which was the rinsed with chloroform saturated with ammonia gas. The combined filtrate was concentrated under vacuum. The residue was concentrated as a solution in toluene for subsequent reaction.

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