Ruthenium Catalysts for Controlled Mono‐ and Bis‐Allylation of Active Methylene Compounds with Aliphatic Allylic Substrates

The allylation of 1,3‐dicarbonyl compounds and malononitrile with aliphatic allylic substrates is achieved under mild conditions in the presence of new ruthenium catalysts. The ruthenium complex [Ru(C 5 Me 5 )(2‐quinolinecarboxylato)(CH 2 CHCH‐ n ‐Pr)] [BF 4 ] as a precatalyst, allows the synthesis of mono‐allylated branched derivatives. On the other hand, the parent complex [Ru(C 5 Me 5 )(MeCN) 3 ] [PF 6 ] as a precatalyst, straightforwardly favours the bis‐allylation of the procarbonucleophiles leading to bis‐allylated bis‐linear products. The involvement of the two precatalysts provides a sequential synthesis of unsymmetrical mixed linear‐branched bis‐allylated derivatives.