| Abstract
| - In the presence of Ru3(CO)12 and Ar-BIAN (bis(arylimino)acenaphthene) as ligand and under CO pressure, nitroarenes react with unactivated olefins to give allylamines in good yields. The reaction mechanism has been investigated, and the catalytically active species is Ru(Ar-BIAN)(CO)2(olefin).
- A reaction is reported, resulting in the allylic amination of an unactivated olefin,cyclohexene, by a nitroarene, catalyzed by Ru3(CO)12/Ar-BIAN (Ar-BIAN = bis(arylimino)acenaphthene), under CO pressure. The reaction involves an intermolecular catalytic C−Hfunctionalization by a transition metal complex. Best results (selectivity up to 81.9%, witha substrate/Ru3(CO)12 ratio = 50) are obtained by using nitroarenes bearing electron-withdrawing substituents and Ph-BIAN as a ligand. Other olefins can also be employed inplace of cyclohexene. The reaction mechanism has been investigated. The reaction is firstorder in nitroarene and olefin, which is used as solvent in most cases, but the rate equationalso contains an olefin-independent term. A rate acceleration by small amounts of toluenein the solvent mixture is due to a faster formation of Ru(CO)3(Ar-BIAN) from Ru3(CO)12and Ar-BIAN in its presence. This last complex is in equilibrium with the active speciesRu(Ar-BIAN)(CO)2(cyclohexene), and its direct reaction with the nitroarene accounts for theolefin-independent term in the rate law. The reaction of Ru(CO)3(Ar-BIAN) with nitroarenesgives Ru(CO)2(Ar-BIAN)(η2-ArNO), which has been isolated in one case, but this complex isnot an intermediate in the synthesis of allylamines. Coupling between a coordinatednitrosoarene and a coordinated olefin appears to be responsible for the C−N bond formation.
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