Catalytic hydroallylation of norbornadiene with allyl formate

Norbornadiene (NBD) reacts with allyl esters All—OC(O)R (R = Me, But, Ph, CCl3, CF3) in acetonitrile solutions of palladium(0) complexes to give a mixture of four isomeric nontraditional allylation products and the corresponding carboxylic acids. Under similar conditions, the reaction of NBD with allyl formate in solutions of Pd0 and PdII complexes occurs selectively, resulting in the product of addition of the allyl fragment and the H atom to an NBD double bond, 5-allylbicyclo[2.2.1]hept-2-ene, and CO2. The hydroallylation of NBD is accompanied by catalytic addition of formic and acetic acids to one double bond of the diene to give bicyclo[2.2.1]hept-2-en-5-ol and nortricyclan-3-ol acetates and formates. Unlike most known palladium-based catalyst systems, these complexes exhibit catalytic activity also in the absence of phosphines.