Selective aryl α-diimine/palladium-catalyzed bis-alkoxycarbonylation of olefins for the synthesis of substituted succinic diesters

Aryl alpha-diimine derivatives have been used,for the first time, as efficient new ligands for the palladium-catalyzed oxidative bis-alkoxycarbonylation reaction of olefins. The most active catalyst was formed in situ from bis(9-anthryl)-2,3-dimethyl-1,4-diazabutadiene and palladium(II) trifluoroacetate[Pd(TFA)2]. This catalytic system was able to selectively convert olefins into succinic diesters in good yields (up to 97%) and low catalyst loading (up to 0.5 mol%) under mild reaction conditions [4 bar of carbon monoxide (CO) at 20°C in the presence of p-toluenesulphonic acid as additive and p-benzoquinone as oxidant] . The optimized conditions could be successfully applied to both aromatic and aliphaticolefins, by using methanol, benzyl alcohol or isopropyl alcohol as nucleophiles.